Realism argues that states seek to increase their power to ensure security. Japan expanded aggressively into China, Southeast Asia, and the Pacific to secure resources and strategic dominance.

Realists emphasize the role of material capabilities in state behavior. Japan sought to control raw materials (oil, rubber, and steel) in Manchuria and Southeast Asia to sustain its military and economy.

Paper tiger myth → irrationality of japanese decisions

The concept of "paper tiger" myths relates to Japan’s overextension before WWII in that Japan misjudged the strength, resolve, and reaction of its adversaries, particularly the United States and Western powers. These myths stemmed from realist miscalculations and overconfidence in Japan’s own power.

1. Irrationality of Japanese Decisions
   • Move into Manchuria
   • Invasion of China
   • Southern strategy
   • Attack on pearl harbor

• War ends with bombing of Hiroshima
  • Facing a naval boycott (not getting enough oil and food)

why they were wrong:

• The U.S. responded with full-scale mobilization after Pearl Harbor, showing it was not a paper tiger but a sleeping giant.
• Japan lacked the industrial and resource base to sustain a long war, making its aggressive realism self-defeating.
• Overextension stretched Japan’s military thin, making it vulnerable to counterattacks.

Realism, with its emphasis on power politics and national interest, provides a framework for understanding Japan's overexpansion leading up to World War II. Here are some examples of how realism is sufficient to explain Japan's actions:

Pursuit of Regional Hegemony Japan aimed to be the dominant power in East Asia, mirroring the United States' hegemony in the Western Hemisphere1. This ambition drove Japan's foreign policy, especially with the crumbling international order1. As the international system changed at the end of the 1920s, the assumptions of the Washington System eroded, and revisionist sentiment grew within Japan2.

Resource Acquisition Japan's leaders believed control of richer territories, such as China, was essential to secure resources for modern warfare3. The Army Ministry concluded that the home islands and existing empire could not provide sufficient resources3.