Immediately after hearing the news of the Japanese attack on Pearl Harbor on 7 December 1941, General George C. Marshall, the chief of staff of the United States Army, directed all commanders in the Pacific to implement war plan Rainbow 5.1 While the plan called for the military forces in the Far East to carry out certain tasks, Rainbow 5 was much more than a blueprint to guide specific responses to enemy aggression. It was the culmination of a planning effort that was years in the making. Even before the Second World War began in Europe with the German invasion of Poland on 1 September 1939, military strategists in the United States were struggling to formulate plans that could successfully guard American interests in any number of international situations. This comprehensive peacetime exercise, which seems so commonplace today, was unprecedented in American history... (Read the full article below)