The conflict between the US and Japan during World War II not only involved the army of those countries and affected the Japanese population on which two atomic bombs, but also to the populations of Japanese immigrants who were based in the Americas were thrown since the late nineteenth century. Since decades before the Japanese attack on Pearl Harbor Naval Base in 1941 hundreds of thousands of migrants became the center of attention wing and monitoring of both powers in order to serve their respective interests. From researching the lives of two immigrants who arrived in Mexico, Masao Tsuru Imuro and Kiso, described in detail the American and Japanese espionage activities in the country