The Mexican Revolution started in 1911; it alarmed American business interests that had invested in Mexican mines and railways. The United States involvement in the Mexican Revolution, include, among other violations of sovereignty, the ambassadorial backing of a coup and assassination of President Francisco I. Madero and the military occupation of Veracruz. Large numbers of Mexicans fled the war - torn revolution into the southwestern United States. Meanwhile, the United States increasingly replaced Britain as the major trade partner and financier throughout Latin America. The US adopted a "Good Neighbor Policy '' in the 1930s, which meant friendly trade relations would continue regardless of political conditions or dictatorships. United States signed up the major countries as allies against Germany and Japan in World War II. However, some countries like Argentina, Chile, Ecuador, Paraguay, Uruguay and Venezuela only joined the Allied side in 1945. The era of the Good Neighbor Policy ended with the ramp - up of the Cold War in 1945, as the United States felt there was a greater need to protect the western hemisphere from Soviet Union influence and a potential rise of communism. These changes conflicted with the Good Neighbor Policy 's fundamental principle of non-intervention and led to a new wave of US involvement in Latin American affairs.
american continued interest in latin america came from an earlier policy known as
Good Neighbor Policy Good Neighbor Policy Good Neighbor Policy