Question

What "four powers" agreed to the Four Power Treaty of 1921?

Answer 1

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Answer 2

The Four-Power Treaty

In the Four-Power Treaty, the United States, France, Britain, and Japan agreed to consult with each other in the event of a future crisis in East Asia before taking action. This treaty replaced the Anglo-Japanese Treaty of 1902, which had been a source of some concern for the United States. In the years following World War I, U.S. policymakers saw Japan as the greatest rising military threat. Heavily militarized and looking to expand its influence and territory, Japan had the potential to threaten U.S. colonial possessions in Asia and the profitable China trade. Because of the 1902 agreement between Britain and Japan, however, if the United States and Japan entered into a conflict, Britain might be obligated to join Japan against the United States. By ending that treaty and creating a Four-Power agreement, the countries involved ensured that none would be obligated to engage in a conflict, but a mechanism would exist for discussions if one emerged.

Answer 3

Source: https://history.state.gov/milestones/1921-1936/naval-conference