War Plan Orange
In light of the events of the late 1930s (the outbreak of the Second Sino-Japanese War, the Molotov-Ribbentrop Pact, and the German conquest of Poland and Western Europe) American planners realized that the United States faced the possibility of a two-front war in both Europe and the Pacific. War Plan Orange was withdrawn, and five "Rainbow" plans were put forward. Unlike the earlier colored plans, which had assumed a one-on-one war, the Rainbow plans contemplated both the possibility of fighting multiple enemies and the necessity of defending other western hemisphere nations and aiding Britain.