How is the Gentlemen's Agreement in 1907 connected to the evacuation of Japanese Americans from the West Coast in 1942?

The Gentlemen's Agreement of 1907 (日米紳士協約, Nichibei Shinshi Kyōyaku) was an informal agreement between the United States of America and the Empire of Japan whereby the United States would not impose restrictions on Japanese immigration and Japan would not allow further emigration to the United States.

the answer would be:

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