While Hitler marched across Europe, the Japanese continued their war in the Pacific. In 1939 the United States dissolved its trade treaties with Japan. In 1940 the American Neutrality Acts cut off supplies of necessary war materials by embargoing oil, steel, rubber, and other vital goods. It was hoped that economic pressure would shut down the Japanese war machine. Instead, Japan’s resource-starved military launched invasions across the Pacific to sustain its war effort. The Japanese called their new empire the Greater East Asia Co-Prosperity Sphere and, with the cry of “Asia for the Asians,” made war against European powers and independent nations throughout the region. Diplomatic relations between Japan and the United States collapsed. The United States demanded Japan withdraw from China; Japan considered the oil embargo a de facto declaration of war.
