In the summer of 1939 Japan was increasingly bogged down in combat with China. As you can see in the map below, Japan controlled not only Manchukuo (Manchuria) but swaths of Inner Mongolia and China. Importantly, Japan also controlled almost all major seaports facing the East and South China Sea. Manchukuo presented its own control issues, largely centered around rampant banditry, but all the other areas required the Kwantung Army (Imperial Japanese Army on the mainland) to provide occupation and policing forces in areas they had conquered. At the same time the Kwantung Army continued offensive operations in Northern China.

Notice that Japan also had an extensive border with the Soviet Union as well as a history of conflict with czarist Russia that extended some 60 years back in time including the 1904-1905 Russo-Japanese War which removed Russian presence in Manchuria and Korea. Russia lost the warm water ports in Darien and Port Arthur, access to the resources of Manchuria, and was often required to transport goods and resources via the Trans-Siberian Railway rather than via ship. In addition Russia was required to cede the lower half of Shanklin Island (just north of Japan). All of this fit into Japan’s “strategic buffer” concept keeping China and Russia/Soviet Union at “arm’s length” from the home islands.

The Nomonhan Incident

Also known as the Battles of Khalkhin Gol, the Nomonhan Incident was a major but undeclared border war fought between Imperial Japan and the Soviet Union’s Mongolian forces from May to September 1939. It occurred along the poorly defined frontier between Japanese-controlled Manchukuo and Soviet-aligned Mongolia. Though officially termed an “incident” by Japan to avoid acknowledging a formal war, the conflict involved tens of thousands of troops, armor, artillery, and aircraft, making it the largest land battle Japan fought before the Pacific War. The fighting ended in a decisive Soviet victory, delivering a shock to the Japanese military and reshaping Japan’s strategic direction on the eve of World War II.

The Background

At the root of the conflict was a disputed, ambiguous border. Japan claimed the boundary lay along the Khalkhin Gol (Halha River), while the Soviets and Mongolians insisted it lay several miles east. The area was remote, sparsely populated, and economically marginal but symbolically important as a test of sovereignty and power. It was also extremely remote from the Imperial Japanese Army (IJA) Staff and Ministry in Tokyo. All of this was simply ingredients of a toxic stew only awaiting the flame to start a boil. And the Kwantung Army was only too happy to ignite the flame.

The Kwantung Army had a well earned reputation for acting autonomously from Tokyo, initiating aggressive actions to force what it believed were the necessary political outcomes, and viewing itself as the vanguard of Japan’s continental destiny. This attitude led to the Mukden Incident (1931), the Marco Polo Bridge Incident (1937), and the quagmire of the Second Sino-Japanese War. By the summer of 1939 the IJA was already stretched thin, had terrible logistics support, and was lacking in combined arms capability – meaning tanks, artillery and ground support from aviation assets. Financially, Japan was stretched thin in trying to keep the IJA funded at the same time funding the Navy’s capital intensive shipbuilding efforts.

Nonetheless, by 1939 the bane of IJA’s existence – an independent, insubordinate junior officer corps believed that controlled escalation against the Soviets could secure Japan’s northern frontier, expand the strategic buffer or even open the door to expansion into resource-rich areas of Siberia. In the view of Japan, the majority of the peoples in Siberia and Mongolia were Asiatic and thus properly best served under the Imperial Protection of the Emperor. They did not bother to ask the people of those areas about their preference.

Northern Expansion Doctrine (Hokushin-ron)

Within Japan’s strategic debates, the Army strongly favored Hokushin-ron, the idea that Japan’s future lay in expanding northward against Russia rather than southward into Southeast Asia. This belief rested on overconfidence from victories in China, an underestimation of Soviet military modernization, and a deep seated anti-communism which was, at this time, being suppressed in the home islands. Nomonhan emerged from a belief that the Red Army could be tested, pressured, and defeated through limited engagement. It was less a grand strategy and more a tactical escalation.

In part it was also pushing back on the evolving southern expansion doctrine being proposed by the Imperial Japanese Navy (IJN) whose interest lay in the resource-rich Southwestern Pacific, especially the oil fields of Borneo, Malay and Java.

The local IJA commanders were confident that Japanese infantry superiority would compensate for weaknesses in armor and logistics. In addition, they believed that the Soviets would avoid a major escalation. The Kwantung Army assumed that a sharp, localized victory would strengthen Japan’s hand diplomatically and militarily.

The IJA horribly misread Soviet intentions. The Soviets retained the memory of the humiliating defeat by Japan of czarist Russia. It was a lingering shame that the Soviets would never let happen again. They were more than willing to fight. They also had superior tanks and artillery and a capacity for combined arms operations with their ground forces. Japan also failed to recognize that the Soviets had the same essential “strategic buffer” view as Japan. Mongolia as part of that buffer and the Soviets would respond decisively to any threat in that region.

Combat

In the period May–June 1939, the initial clashes involved cavalry and infantry skirmishes for small areas of land as well as an island in the middle of the border river. Japanese forces crossed into disputed territory, driving out Mongolian units. Early successes reinforced Japanese confidence.

In June, the Soviets appointed General Georgy Zhukov to command. Zhukov rose to prominence with his leadership at Nomonhan. He was a brilliant tactician and field commander later becoming the most prominent and successful Soviet military commander during World War II often credited as the key strategist behind major Eastern Front victories against Nazi Germany. He rose to the position as Chief of the General Staff and a Marshal of the Soviet Union, leading the defenses of Moscow, Leningrad, Stalingrad and commanding the final assault on Berlin. He was formidable. 

Long story, told short, Zhukov prepared a coordinated counteroffensive rather than piecemeal retaliation, amassing artillery, tanks, and aircraft supported by secure logistics/supply lines. In late August, Zhukov launched a classic double-envelopment, using tanks and mechanized infantry to encircle Japanese forces who lacked effective anti-tank weapons, were undersupplied, and relied on infantry assaults against armor. The result was catastrophic. Entire Japanese formations were destroyed or rendered combat-ineffective. It was a clear battlefield defeat involving some 20,000 Japanese casualties with the loss of experienced officers and elite units. Japan agreed to a ceasefire in September 1939, restoring the status quo but psychologically, the damage was done. It was the first unequivocal defeat suffered by Imperial Japan since the Meiji era.

Unintended Consequences

Nomonhan should have shattered Japanese assumptions – but it did not. Japan continued to believe that Japanese fighting spirit and bushido were enough to triumph and could overcome material inferiority and weak logistics. This would plague them all the way through 1945. They also continued to believe that wars could be tightly controlled and limited.

The defeat decisively undermined the Northern Expansion faction within the Army. After 1939 all plans for war against the Soviets were shelved, a defensive posture was adopted along the Manchurian frontier, and Japan avoided conflict with the Soviets for the remainder of WWII. This shift paved the way for Nanshin-ron (southern expansion), pushing Japan toward Southeast Asia and the Dutch East Indies’ oil. It was the path to confrontation with Western colonial powers. In this sense, Nomonhan helped set Japan on the road toward Pearl Harbor.

Perhaps the most profound unintended consequence was for the Soviet Union. Stalin gained confidence that Japan would not attack in the east and soon enough the two nations signed the Soviet–Japanese Neutrality Pact (1941) allowing Soviet divisions to later be transferred west to defend Moscow against Germany. The Nomonhan incident influenced the outcome of the European war, not just Asian geopolitics.

The Nomonhan Incident stands as a warning ignored about the limits of aggression driven by ideology rather than sound political and military strategy and tactics. It revealed the dangers Clausewitz warned of: wars initiated for political symbolism without a clear path to decisive victory would ultimately end in disaster for those who initiated the action.

Nomonhan was not merely a border clash. It was Japan’s strategic crossroads. Historians have come to now recognize Nomonhan as one of the most consequential “incidents” of the twentieth century – even though it largely remains unknown in the West.

Image credit: various photographs from Naval Aviation Museum, National World War II Museum, and US Navy Archives. | Pacific area map of 1939 courtesy of MapWorks via Wikipedia Commons.

After the Marco Polo Bridge Incident (July 1937)  the United States took measured but meaningful actions in support of China, while still stopping well short of alliance or military intervention. The pattern is best described as moral, diplomatic, and limited material support, shaped and heavily limited by existing U.S. neutrality laws and the general sense of isolationism among the American people and Congress.

Given the mood and legal constraints facing the Roosevelt administration there was little to be done if the goal was to avoid military actions. What actions were taken are best described as nonrecognition and positioning. To that end the U.S. refused to recognize Japanese territorial gains in China, continued to uphold and advocate the Open Door Policy regarding commercial trade with China, and treated China as the legitimate sovereign power throughout the conflict.

This stance mattered because it denied Japan international legitimacy as virtually all nations followed the U.S. lead in this matter. It also gave China an enhanced standing in international diplomatic forums. The actions, limited as they were, did signal U.S. sympathy without military commitment. While Secretary Cordell Hull worked the diplomatic world, striking a balance that applied limited international pressure in a moral sense to Japan, he also had to temper calls from Britain for concrete economic sanctions. Britain was at the threshold of war in Europe (which began September 1939) and was concerned with Japanese aggression in the Asia Pacific area against British colonies and interests.

A Divided Asian Policy

In the post “American Diplomacy in 1937” we considered some of the key figures in determining the U.S. diplomatic response to Japanese aggression in China: President Franklin D. Roosevelt; Cordell Hull, Secretary of State; Stanley Hornbeck who headed the Far East Department; Nelson Johnson, Ambassador to China; Joseph Drew, Ambassador to Japan; and key advisors to Hull – J. Pierpoint Moffat and Hugh Wilson. Moffat was the son-in-law of Joseph Drew. Wilson had served in Japan in the mid-1920s.

Roosevelt, Hornbeck and Johnson can be viewed as members of an “activist camp” although in varying degrees. Hull, Grew, Moffat and Wilson would be viewed as members of a “don’t aggravate Japan” camp who wanted to confine U.S. responses to diplomatic channels while avoiding economic sanctions of any form as well as military action. At this point “military action” primarily meant action by naval and marines forces stationed in Shanghai as protection of U.S. citizens and interest in Shanghai’s International Settlement as well as citizens and interests upstream on the Yangtze River.

Hull’s position was to do nothing to antagonize Japan but nothing to assist them either. President Roosevelt did not like Hull’s Asian policy. While he accepted them as prudent the President was frustrated by a policy that let Japan get away with blatant aggression. Roosevelt was known to keep his own counsel and on occasion “go his own way.” In October 1937 he gave what came to be known as the Quarantine Speech that implicitly condemned Japan’s aggression (alongside Italy and Germany). In the speech he framed Japan as a disturber of international order but deliberately avoided naming Japan to prevent escalation. But his meaning was clear: “The present reign of terror and international lawlessness… [means that] the very foundations of civilization are seriously threatened…international anarchy destroys every foundation of peace…This situation is of universal concern.” Roosevelt went on to compare the terror and lawlessness to a contagion becoming an epidemic and note that the only reaction to an epidemic is quarantine. “War is a contagion, whether it be declared or undeclared…There must be positive endeavors to preserve peace.”

The speech did everything that Hull was trying to avoid. First, it exacerbated diplomatic relations with Japan. Although Roosevelt never named Japan, Japanese leaders and the press immediately understood that Japan was one of the principal targets. From Tokyo’s perspective, the speech signaled that the United States was morally siding with China, Japan was being described as a threat to international order, not merely a regional power pursuing interests, U.S. neutrality was becoming conditional rather than detached, and this signaled a shift from U.S. disapproval to U.S. warning.

The Japanese Foreign Ministry responded with measured, non-confrontational statements. This restraint reflected a desire to avoid provoking sanctions, an awareness that Japan still depended heavily on U.S. trade, and a hope that American isolationism would reassert itself. In the Cabinet it was viewed as a trial balloon for later economic sanctions. Within the military it added to the view that the U.S. viewed them as a second-rate nation. The Japanese Army dismissed it as moralizing. Within the Navy the speech confirmed fears that American opinion was shifting and that the current moral pressure could evolve into economic or naval measures – but still considered armed conflict years away.

Hull was also concerned that the speech would have the western signatories to the Nine Power Treaty call for an international conference (which it did) and that the U.S. would be thrust into the leadership role. Within domestic politics/policy it marked the beginning of a division within the nation’s foreign policy with Roosevelt pushing for something more dynamic and assertive – and yet not giving any concrete substance to the notion – while at the same time Hull was trying to maintain the established policy. 

This difference would prove to be somewhat problematic as Roosevelt tended to think in broad, sweeping terms while avoiding detailed plans. Hull tended to think in categories of fundamental goals without incremental steps towards that end.

Proposals and Next Steps

Among the activists, Hornbeck shared Hull’s conviction that diplomatically Japan was not an honest dialogue partner, but also understood Japan’s foundational interests: economic and political security in her area of interest. While much of the U.S. Department of State believed Japan had “taken on more than it could chew,” Hornbeck understood that with every bite, Japan’s appetite increased, but that there were very different levels of “appetites” between the nationalist/militarists in Japan and their moderate counterparts in civil governance and diplomacy. Hornbeck wanted to actively approach Japan with the “carrot” that would give them the security they desired, but needed a “stick” to forestall further Japanese aggression in China. In this he was aligned with President Roosevelt, but the President in 1937 did not believe he had the support of either Congress or the public for any form of “carrot.”

While the U.S. internal debates continued and Japan aggressively moved in China, an element of the Japanese government initiated “feelers” from offices in Tokyo, Washington DC, and Paris. They wanted to see if the U.S. would help present Japan’s terms for peace and moderate Sino-Japanese talks. Unfortunately, Japan’s offer matched their history of vague diplomacy, asking for specific current actions from China while pinning their commitments to future events that might or might not happen. Ambassador Grew in Japan, in general more positive about Japan than others, acknowledged that his analysis of the terms to China were really full capitulation couched in ambiguous language. Grew attempted to get Japan to commit to “details” consistent with the Nine Nations Treaty of which Japan was a signatory. Eventually the initiative “died on the vine.”

By December 1937, Treasury Secretary Morgenthau, of a like mind with Roosevlet and Hull, raised the possibility of beginning to seize Japanese assets held in the U.S. as a first step. Roosevelt was initially keen on the idea, but by late January 1938 that initiative “died on the vine.”

There were other initiatives but in the end all suffered the same fate. The U.S. was not able to field a policy for Japan other than Hull’s “don’t aggravate, just wait.” Some of the division and lack of action was certainly tied to U.S. politics with the American people largely isolationists, still suffering from effects of the Great Depression, and mid-term elections being close by. But a good deal was connected to the divisions with the State Department.  Ambassador Grew, long serving in Japan, had a belief in the moderates of the party – people he had known since the 1920s. Historians agree that he placed too much emphasis on the standings of the moderates, who by the 1930s were largely sidelined.  With Washington DC, the Far East Department (FED) firmly believed that the nationalists and military elements held key control of Japan’s policies. FED believed that Japan had not only regional but global aspirations and foresaw in the spring of 1938 that Japan would formally partner with Germany and Italy – which they did in the September 1940 Tripartite Treaty.

By the Spring of 1938, China was holding its own…to some degree. Hull concluded that Japan was overextended, lacked the resources to capture China, much less control China, and concluded that Japan would never win the war. And that they might even lose the war over time. This “betwixt-and-between” view was supported by General Joseph Stillwell, US Army, an advisor to Chiang Kai-shek.  The next effect was to further convince Hull that his policy of waiting while not aggravating Japan was the right course of action.

As a result, a routine was established:  Japan took some action which required Ambassador Grew to protest. Japan offered conciliatory words with no concrete actions apart from a renewed request for the U.S. to moderate peace talks (as before). In the end, with no actions forthcoming, the U.S. would formally protest. Japan did not respond.  It was a cycle of rinse and repeat as each incident came along.

In May 1938, Japan initiated a campaign of strategic bombing of Chinese civilian populations. This campaign was extensively covered by U.S. news outlets and American missionaries. At the movies, new reels and reports of the campaign were seen by the American public. It is estimated that in 1938, in urban America, the average adult saw two movies in-theatre each week. It did not take long for a wave of public outcry to arise. From that came the calls for U.S. companies to stop their “blood trade” with Japan. The outcry forced Hull to initiate a “moral embargo” asking U.S. companies to voluntarily stop trade with Japan in aircraft, aviation maintenance items, aviation fuel, and key resources and tools needed for the production of war goods. Hull’s goal was to calm the U.S. public.  At the same time Hornbeck and other departments in State wanted the U.S. to abrogate the 1911 U.S.-Japan Trade Agreement.

The war in China continued through the summer and into the autumn. The Chinese lost the city Xuzhou at the end of May but the battle proved the Chinese strategy of attrition that increasingly made Japan pay an ever increasing costs in terms of casualties and equipment. The Japanese were drawn into the Battle of Wuhan which involved over 1 million soldiers and great loss, but marked the end of Japan’s rapid advance and the beginning of a long-term strategic stalemate. This advance was also forestalled when Chinese forces breached the dikes of Yangtze River, creating a massive, man-made flood to block the Japanese advance.

In November 1938, the Prime Minister of Japan, Prince Konoe, gave what is called the “New Order” speech that made public what the Far East Department (FED) had long promoted – Japan’s ambitions were super regional and also global. This was the start of a coming change within the State Department, the Treasury Department and Congress to make loans to China and begin to discuss abrogating the 1911 U.S.-Japan trade agreement. Withdrawing from this agreement made later sanctions and embargoes possible.

Of interest is also at this time, Ambassador Grew was vacationing in the United States, and when asked the Charge of Affairs Doorman reported that the military and nationalists were in complete control of the governance of Japan. This March 1939.

Image credit: various photographs from Naval Aviation Museum, National World War II Museum, and US Navy Archive

So far in this series we have worked our way up to 1937. From the summer of 1937 until Pearl Harbor the conflict in mainland China is the dominant factor that drives and animates Japan’s relationships (or lack thereof) with China, the United States, Britain, the Netherlands, and all the nations of the Asia-Pacific region. The ebb and flow of this conflict known as the Second Sino-Japanese War is really the beginning of the Asia Pacific War that will become World War II upon the 1939 outbreak of war on the European continent and the entry of the United States into the war after the attack on Pearly Harbor in December 1941. 

The Second Sino-Japanese War began not as a formally declared conflict but as a local military clash that escalated beyond political control, reflecting the structural weaknesses of both Chinese sovereignty and Japanese civilian authority over the Imperial Japanese Army (IJA). From the Marco Polo Bridge Incident in July 1937 to the summer of 1941, the war evolved from a short punitive campaign into a protracted, brutal struggle that reshaped East Asia and set Japan on an increasingly irreversible path toward wider war.

The Marco Polo Bridge Incident and the Slide into War

Since 1905 and the Boxer Revolt in China, foreign nations, including Japan, had the right to station troops to protect their nationals and legations. For the Japanese this included guarding key railway lines connecting Beijing to the port of Tianjin. The Marco Polo Bridge spanned the Yongding River and sat on the main rail and road routes linking Beijing and Tianjin. As such it was of high strategic importance to Japan and a tactical chokepoint. Because of this Japanese units frequently patrolled and trained nearby. Night exercises were common and technically permitted under treaty arrangements.

On July 7th, Japanese troops were conducting a night training exercise near the bridge when one soldier failed to return, Japanese officers suspected detention by Chinese forces and demanded entry into a local city to search for their comrade; the Chinese refused. Shots were exchanged, and the situation escalated.

Similar incidents had occurred before and had been defused diplomatically. What made 1937 different was not the presence of troops, but the political climate surrounding the incident.

By 1937 Chiang Kai-shek’s coalition of northern and central warlords was deemed to be weakening in the view of the Japanese. This gave the Japanese field commanders (junior officers) the opportunity to aggressively respond as was their inclination. As discussed previously, by this time the field commanders knew that the civilian leaders in Tokyo were reluctant to restrain the Kwantung Army and so they pressed ahead. But they had misread the resolve of the Chinese leaders. So to speak, this time the incident was a bridge too far. The system that once contained incidents had broken down. Neither side was willing or able to step back once violence occurred. Mutual distrust, heightened nationalism, and the absence of firm political restraint allowed the confrontation to spiral.

Neither Tokyo nor Nanjing initially sought full-scale war. Japanese civilian leaders hoped to localize the conflict, while Chiang Kai-shek remained cautious, wary of Japan’s military superiority. Yet Japanese field commanders continued to press forward, and political leaders in Tokyo, fearful of appearing weak and constrained by past precedents of insubordination, ratified military escalation rather than restraining it.

By late July, Japanese forces had seized Beijing and Tianjin. What might once have ended in diplomatic compromise instead became a test of national will.

Shanghai and the Expansion of the War

The conflict escalated dramatically with the Battle of Shanghai (August–November 1937) a key seaport and source of income to the Chinese government. The Marco Polo Bridge incident ignited the conflict; Shanghai made it irreversible. Before August 1937, both governments still claimed to want containment and find a “local solution.” But locally, the Japanese approach into the region was a punitive campaign initiated by local field commanders and Shanghai was the goal.

Shanghai was China’s economic and financial center. It was a major port for foreign trade and it controlled the Yangtze River which was the “highway” into Central China. By 1937, Japan had a large civilian population and commercial interests in Shanghai including banking and shipping. As well, Japan had naval facilities and marines stationed in their part of the International Settlement. Any fighting in or near Shanghai could be framed as protecting Japanese nationals and treaty rights giving them a legally defensible pretext for military involvement. The hope was to draw Chiang Kai-shek into battle, force him to negotiate resulting in a collapse of Chinese Nationalist morale, and bring the war to a quick end. This reflected a persistent Japanese belief that China would not endure sustained pressure. That working theory had not proved true in Manchuria which Japan still struggled to control. It would not provide true now nor would it prove true at any point over the next 8 years.

Chiang Kai-shek understood the Japanese intent and chose to commit his best German-trained divisions in China’s most international city.  His aim was to demonstrate Chinese resistance to the international community with its large contingent of foreign press and media. While the Marco Polo Bridge was “out of sight”, Shanghai would force Japan to fight in full view of the world. Video of the fighting became a staple in US movie theatres in the news trailers that preceded the feature film. Chiang hoped the result would be foreign mediation and that they might intervene diplomatically.

Japan responded with overwhelming force, deploying naval, air, and ground units. Once fighting began, Japanese prestige and military logic demanded escalation rather than withdrawal. The battle became one of the largest and bloodiest urban engagements of the interwar period. Although Japan ultimately captured Shanghai, the cost in casualties, time, and resources dashed Japanese assumptions of a quick victory. But it did not extinguish the IJA’s optimism about the glory or destiny of the war.

The Shanghai campaign marked a turning point as the war became total in scope, involving mass mobilization on both sides. At home as the Japanese press reported success while not reporting the tremendous losses, Japanese public opinion increasingly supported the war and the Army, making it even more difficult as diplomatic compromise became increasingly untenable. The intentional strategic bombing of civilian areas as a means of breaking morale exacerbated the breakdown.

Shanghai became a symbolic test of national honor. In China, the battle unified the Chinese factions in the common cause against Japan – even the Communists joined. In Japan, the narrative fed into the State Shinto program that the Army’s sacrifice demanded public support and sacrifice all the way to victory.

After months of brutal fighting any compromise would be perceived as betrayal as the war became morally and emotionally entrenched in the psyche of the nations. There were no diplomatic off-ramps. Japan rejected mediation efforts and were on the road to total victory. China could not accept terms without sovereignty remaining intact. Historians often note that before Shanghai, war was possible. After Shanghai, peace was politically unimaginable.

Nanjing and the Descent into Atrocity

Following the fall of Shanghai, Japanese forces advanced up the Yangtze River toward Nanjing, then the capital of the Nationalist government. The city fell in December 1937, after Chiang Kai-shek had withdrawn the government inland to Wuhan.

What followed, the Nanjing Massacre (also known as the Rape of Nanking) became one of the most infamous episodes of the war. Over several weeks, Japanese troops committed widespread atrocities, including mass killings, rape, and looting. Estimates of the dead range from tens of thousands to over two hundred thousand.

The significance of Nanjing extended beyond the immediate horror. It destroyed Japan’s international reputation, hardened Chinese resistance, made negotiated peace politically impossible for Chiang Kai-shek, and deepened Japan’s moral and diplomatic isolation. Within Japan, however, the massacre did not provoke accountability; rather, it was subsumed beneath censorship and nationalist narratives, reinforcing the pattern established after earlier acts of military excess.

Nanjing was the most visible atrocity of the Second Sino-Japanese War, but it was only one episode in a broader pattern of mass killing, terror, and repression that unfolded across China from 1937 to 1945. Most historians agree that atrocities were systemic, not accidental and that violence escalated as Japan failed to secure quick victory. The dehumanization of Chinese civilians became embedded in military practice and was demonstrated in the 1938 Wuhan Campaign and Yangtze Valley operations, the Sankō Sakusen  (kill all, burn all, loot all) policy in Chinese Communist areas from 1940-1943, the 1943 Changjiao Massacre, and the list goes on.

Stalemate and the Failure of Decisive Victory

By early 1938, Japan controlled China’s major cities, ports, and railways but not China itself. The Nationalist government retreated first to Wuhan, then to Chongqing, deep in China’s interior. From there, Chiang adopted a strategy of protracted resistance and giving up territory to garner time while the Japanese were stretched even thinner. At the core, Chiang relied on China’s vast geography and population.

Japan faced a growing dilemma as military success did not translate into political control. The vastness of their conquest and occupation required ever-larger troop commitments. The IJA had been modeled on the Prussian system, and yet Japan failed to understand the noted war theorist, Hans Clausewitz who argued that merely occupying territory is not the same as defeating an enemy. If an occupier controls cities, roads, and fortresses but fails to destroy the enemy’s army, government, or will to resist, the population will turn to partisan guerrilla warfare. Such resistance can and will bleed the occupier over time, even when conventional victory seems complete. The fall of Wuhan in October 1938 failed to end the war. Instead, Japan found itself trapped in what many leaders privately acknowledged as a “China quagmire”, though publicly they insisted on eventual victory.

Ideology, Policy, and the Deepening War

As the war dragged on, Japan’s political and ideological posture hardened. In January 1938, Prime Minister Konoe declared that Japan would no longer deal with Chiang Kai-shek’s government, foreclosing diplomatic settlement. This decision, often cited by historians as a critical error, was driven by military pressure, nationalist public opinion, and the belief that China would eventually collapse internally. In practice, this policy eliminated Japan’s best chance for a negotiated exit.

Japan attempted instead to construct a “New Order in East Asia”, envisioning China as a subordinate partner under Japanese leadership. In reality, this meant expanded occupation, collaborationist regimes, and intensified repression.

Throughout this period, the United States remained formally neutral, but increasingly sympathetic to China. American responses included moral condemnation of Japanese aggression, loans and limited aid to the Chinese government, and growing public outrage after incidents such as the Panay Incident (1937) when the Japanese sank a U.S. gunboat involved in rescue operations of U.S. citizens along the Yangtze River. However, until 1940, U.S. actions remained cautious, constrained by isolationism and legal neutrality. Japanese leaders interpreted this restraint as reluctance to intervene militarily, reinforcing the belief that the China war could continue without provoking direct conflict with the United States.

The Road to Wider War, 1939–1941

By 1939–1940, the war in China had become institutionalized. Japan had mobilized society for long-term conflict. Military influence over government had deepened and political dissent was suppressed. The outbreak of war in Europe in 1939 altered Japan’s strategic calculations. With France defeated and Britain embattled, Japan turned increasingly toward southern expansion, while continuing the China war without resolution.

In 1940, Japan signed the Tripartite Pact with Germany and Italy, further alarming the United States. American responses escalated gradually to include export controls on aviation fuel and scrap metal, increased support for China, and increased strategic planning for potential conflict with Japan. In July 1941, Japan’s occupation of southern Indochina prompted the United States to impose a freeze on Japanese assets and an effective oil embargo. By this point, Japan was fighting an unwinnable war in China while facing mounting pressure from the world’s leading industrial power.

From the Marco Polo Bridge Incident to the summer of 1941, the Second Sino-Japanese War evolved from a local confrontation into a protracted, brutal, and strategically disastrous conflict. Japan’s inability to control its own military escalation, combined with nationalist ideology and structural flaws in governance, transformed early victories into long-term overextension. For China, the war became one of survival, unity forged through suffering. For Japan, it became the central trap from which all subsequent decisions would follow: southern expansion to the Southwest Pacific region, confrontation with the United States, and ultimately the full Asia Pacific War.

Image credit: various photographs from Naval Aviation Museum, National World War II Museum, and US Navy Archives.

It would be a herculean task to consider all the elements and forces in the boiling pot that was the Asia Pacific region in the summer of 1937. And even then to understand the levers available to the U.S. to affect the military action in China and Manchuria that was initiated by Japan. Historians argue for or against financial leverage, military leverage, diplomatic leverage and a host of other factors. A book has been written that argues a coalition of merchant shipping companies could have been assembled that could have been effective in controlling Japan because of Japan’s dependence on foreign-flagged merchants to deliver even basic food items. Perhaps the most often discussed topic is that the United States missed a window of opportunity to broker peace between China and Japan that would have set in motion a chain of events so that the United States was never drawn into the war against Japan.

Background: US Foreign Policy

The priority of the President of the United States and the State Department was Europe and the rise of fascism in Italy and Germany, as well as the ongoing Spanish Civil War which was seen as a proxy for the coming conflict in Europe. It was also the priority for Britain and during this period they exerted diplomatic pressure to ensure the U.S. kept Europe as the priority. Nonetheless, the U.S. needed to pay attention to the Asia-Pacific region because of interests in China, the Philippines, Guam and elsewhere.

Some of the key players at the U.S. State Department were: Cordell Hull, Secretary of State; Stanley Hornbeck who headed the Far East Department; Nelson Johnson, Ambassador to China; Joseph Drew, Ambassador to Japan; and key advisors to Hull – J. Pierpoint Moffat and Hugh Wilson. Moffat was the son-in-law of Joseph Drew. Wilson had served in Japan in the mid-1920s.

Hull shared a view with Hornbeck: Japan was not trustworthy given their history of vague diplomacy, military aggression apart from civilian control, and a habit to ask specific current action of the U.S. while pinning their commitments to future events that might or might not happen. By the 1930s they were not considered to be forthright in their diplomacy. In the 1920s, when there was a strong current of liberal democracy, Japanese diplomats were effective – perhaps because the western nations (i.e., U.S. and Britain) achieved their goals. Meanwhile, at home, the military/nationalist parties considered the diplomats to have harmed Japan in strategy and in honor. By the 1930s, it was this latter group that dominated internal and external politics and policy, even as Japan’s diplomatic core retained career people from the 1920s. 

It must be noted that even at this point in history (1937), the U.S. had already broken the Japanese diplomatic cables and traffic (not the military). The U.S. was often reading diplomatic correspondence before the intended Japanese recipient. The distrust was rooted, not only in experience with Japan’s diplomacy of the 1930s, but also with evidence of current intentions revealed in the diplomatic cables.

Perceptions within the State Department

While Hull and Hornbeck agreed it was appropriate to be very cautious in dealing with Japan, where they were not on the same page as regards to “the next steps.” Hull was very much a diplomat who was pragmatic but at the same time was more interested in a lasting settlement rather than incremental steps to such a settlement. His emphasis was always on fundamental principles.  Hull’s experience with Japan was they negotiated to keep options open, were reluctant to commit to hard action, dates and consequences, and most often replied with vague ideas or contingent events whose outcome was rarely knowable.  In addition, the principled but pragmatic Hull believed that the U.S. did not have adequate naval assets to project power to the western Pacific; did not have substantive national interests in China to warrant the threat of military action; understood that any action taken in the summer of 1937 had zero popular support; and that the U.S. did not possess sufficient financial leverage to entice/force Japan to modify its China program. Hull did note in correspondence that “Japan’s invasion of China was not desirable but not intolerable.” 

Hornbeck and Johnson believed that Japan’s aggression would never be limited to China but would eventually expand to include the Southwest Pacific, especially the oil rich nations. Japan wanted diplomatic and trade action that would legitimize their expansive actions, both categories of which were turned down by Hull and President Roosevelt. Hull’s position was to do nothing to antagonize Japan but nothing to assist them either. Roosevelt’s position was harder to pin down. He would agree that the U.S. should do nothing to aggravate Japan, then he would make a very public speech, e.g. Chicago 1937, when we would openly criticize Japan’s aggression and seem to call for a “moral embargo” from U.S. citizens and companies to not buy Japanese goods. In any case, there was nothing concrete that was offered to mitigate Japan’s actions – and that was, in part, due to pressure from Britain and the Netherlands who had substantive interests and holding in the Southwest Pacific – the very target of Japan’s attention.  

The Neutrality Acts

The U.S. was also constrained by the Neutrality Acts. By 1937 the acts prohibited arms sales to all belligerents – in this case China and Japan. It was designed to keep the U.S. isolated. This initially gave Japan a freer hand in its aggression against China without fear of U.S. intervention. Following the outbreak of the Second Sino-Japanese War in 1937, President Roosevelt did not invoke the Neutrality Acts, arguing that no formal declaration of war had been made. This allowed the U.S. to avoid hindering China’s defense, allowing for the shipment of arms to China, which frustrated Japan.

The 1937 Act introduced cash-and-carry, allowing the sale of non-lethal, and later other goods, if paid for upfront and transported by the buyer. While this technically allowed Japan to purchase supplies, Roosevelt selectively used this to enforce a moral embargo on aircraft sales to Japan. Revisionist historians (and what this often means is just the 2nd wave of historians) see this as escalating tensions, making diplomatic resolution difficult. Or as some argue, impossible, as it forced Japan to choose between abandoning its expansionist goals or initiating war to secure needed resources. 

This latter line of reasoning continues as time moves into 1941 concluding that every action of the U.S. to limit Japan’s ability to buy scrap steel, key material resources, aviation fuel, freezing of U.S. held Japanese financial resources, and eventually a complete oil embargo – all “caused” Japan to start the war. In the several books with trajectories along this line (Utley’s Going to War with Japan 1937-1941 and Miller’s Bankrupting the Enemy) while interesting insights and historical details are offered, the analysis seems to miss that Japan had options. In 1937, military spending was 45% of Japan’s national budget and would grow to 65% by 1940; in the United States military spending was 3% (1937). There was more than enough budget for Japan to focus on becoming a commercial powerhouse (as it became post WW2). The currents of history led Japan to become a nation with an outlook on the world similar to Nazi Germany. There is also little to no mention of the rapidly growing death toll in China among civilians and the devastation of cities and economies.

Bankrupting the Enemy acknowledges that the Japanese leadership justified the war as self-defense against the United States, who was trying to strangulate and pauperize Japan and that this was the prevailing view among the majority of government/military leaders in Japan at that time who controlled the nation. Going to War with Japan 1937-1941 notes that Grew, Moffat and Wilson were in contact with the Japanese government who wanted the U.S. to approach Japan offering to moderate a peace settlement with China. True, but in reality they were only in dialogue with the moderate wing of Japanese politics who held no influence within the cabinet, the Diet, the military, and little if any with the Imperial household. The revisionist view seems to base their conclusions of causality on “if only we’d given the moderates a chance…” It is simply near impossible to hold that view if one understood the body politic of Japan from 1937-1941. 

The Contingent Window

A missed opportunity? Was there a window to bring peace to the Asia-Pacific region and avoid the carnage and destruction that happened from 1937 to 1945? Most historians agree that by late 1937 the political, military, and ideological conditions in Japan made a negotiated peace exceedingly unlikely, extraordinarily difficult, though not theoretically impossible even then it was only for the briefest window of time. 

There was indeed a moderate faction in the autumn of 1937 but it was fragile and divided. They included people associated with Prime Minister Konoe, a member of Japanese royalty, and considered by those connections to have access to the Prime Minister. As well there were diplomats in the Foreign Ministry, some officers in the Naval Staff worried about overextension and potential engagement with the U.S., and some Army Staff officers whose primary responsibility was logistics. All in all it was not a prestigious or influential group. It should also be noted that Konoe, as Prime Minister, was an animator for even more aggressive actions in China. As a group they were not cohesive in their aims, lacked control over field commanders, and would not act openly against the tide of nationalism.

Even at its strongest, the moderate camp faced structural barriers – first among them was the autonomy of the Army.  Field commanders often acted independently and civilian leaders could not guarantee compliance. At the same time, the war already enjoyed genuine public support, especially after early successes. Arguments again the war risked accusations of betrayal in a milieu when assassinations were not unusual. And lastly, and most importantly, the war already had Imperial legitimacy. Once the Emperor sanctioned operations, reversal became politically perilous for all involved.

Even if Japan’s moderates could convince a larger element of their own government to be receptive, the U.S. lacked any real means of leverage without economic sanctions or military force, both of which were never policy options for the U.S. Two other factors the moderates did not consider were: there was no U.S. domestic support for assertive involvement and it was likely that even an offer of American mediation risked being dismissed as hostile interference.

Was there a window of opportunity for a negotiated settlement in 1937? Theoretically, yes. Realistically, no and what is really meant is “Sure, occasionally “Hail Mary” passes work in football…but…”

By early 1938, the opportunity, if it ever existed, had effectively vanished.

The “lost moment” assertion is not absolutely wrong, but it vastly overstates the cohesion and power of Japanese moderates and underestimates the force of nationalism, military autonomy, and momentum. 

Image credit: various photographs from Naval Aviation Museum, National World War II Museum, and US Navy Archives. |