In the end, fearing it risked outright war with Japan, the Roosevelt administration held back from offering official military support for Chiang despite professing sympathy for China. Indeed, until America’s entry into the war in 1941, 80 percent of all foreign aid to China came from the Soviet Union. Even after Pearl Harbor, Roosevelt pursued a policy of Europe first, regarding China as a secondary theater of operations and, therefore, warranting no serious US troop presence.
