Japan attempted to advance into Mongolia but was repelled by the Soviet Army in the Nomen Han incident.
The Soviet Union opted to maintain neutrality regarding Japan while focusing on Nazi Germany during World War II.
Japan launched an aggressive campaign against Nanjing (Nanking), resulting in horrific violence and crimes against humanity.
Thousands of civilians were murdered, leading to deep-seated resentment in China due to Japan's lack of repentance.
The involvement of an American gunboat, the Panay, during the atrocities further escalated tensions between the U.S. and Japan.
The Panay was attacked by Japanese planes, leading to casualties among American servicemen, making the conflict personal to the U.S.
Media coverage highlighted the violence against civilians and the attack on the Panay, intensifying American public outrage.
Protests arose in the U.S. against selling materials to Japan, linking Japanese aggression in China to American commerce.
Diplomatic relations between Japan and the United States were already strained, partly due to earlier U.S. actions like the annexation of Hawaii to prevent Japanese expansion.
The U.S. demanded Japan's withdrawal from China, leading to economic sanctions, including asset freezes and trade embargoes on steel and oil—critical resources for Japan.
Japan's military felt compelled to act as they struggled with limited resources due to embargoes, realizing they could fight a war for only about a year.
Despite awareness of U.S. military power, Japan executed a plan to attack Pearl Harbor, aiming to weaken the U.S. Navy enough to prompt American capitulation.
Japan sought to expand its empire and establish itself as a world power comparable to Western nations.
They aimed to control the Pacific region, eliminating American and British influence in Asia.
The Japanese intended to drive European colonial powers out of Asia, which resulted in some success post-World War II.
In countries like China, the legacy of Japanese occupation is largely viewed negatively due to wartime atrocities.
Conversely, some nations such as Indonesia and Malaysia have a more nuanced view of Japanese rule, where Japanese officers trained local forces to resist Western colonial powers.
Japanese military presence laid groundwork for post-war independence movements in various Southeast Asian nations, illustrating complex historical narratives.