Lesson 1: The Growth of U.S.–Japanese Hostility, 1915–1932

Japanese soldiers attacking German soldiers at the German port of Tsingtau.
The Japanese attack on Pearl Harbor had its origins in a growing antagonism between the United States and Japan that first developed during World War I. Japan claimed a special "sphere of influence" in China, in which it would have economic, and even to some extent political dominance. Americans, however, stood for the principle of the "Open Door"—that all countries should have an equal opportunity to market their products to the Chinese. By the late 1920s Japan was in the midst of an economic crisis, and in 1931 seized the rich Chinese province of Manchuria. The foundations were fully laid for a full-scale showdown with the United States.
Using contemporary documents, students in this lesson will explore the rise of animosity between the United States and Japan. It will begin with Japan's "Twenty-One Demands" on China during World War I, and will continue through the Manchurian Incident of 1931.
Guiding Questions
What accounts for the growing hostility that had developed between the United States and Japan by the early 1930s?
Learning Objectives
Explain how Japan's ambitions in China conflicted with the American concept of the "Open Door."
Discuss the means by which the United States and Japan sought peaceful means of resolving their differences.
Articulate why U.S. trade and immigration policies angered the Japanese.
Explain the importance of the Manchurian Incident of 1931, and the American response to it, for the deterioration in U.S.–Japanese relations.