A most important event in World War II. When World War II broke out, with the German invasion of Poland, the United States made a very firm resolution to stay out of this new European War. We had suffered serious casualties in World War I and had gotten little to nothing for it. Part of little to nothing was the Senate, led by Senator Lodge, refused to ratify the League of Nations treaty that Wilson brought home from Paris. Be that as it may, the Americans were NOT going to join another European war, no matter what. The American establishment, starting with President Franklin Roosevelt and working down, saw Hitler as an existential threat and wanted to deal with him. But the voters were dead set against that idea, and Roosevelt, probably the strongest 20th century president, was unable to change voter’s minds.
Pearl Harbor changed all that, overnight. The word that the Japanese had sunk our battle fleet, with 2400 casualties, in time of peace, with out a declaration of war, was infuriating. The country went from isolationism to “let’s fix the Japanese” in less than a day.
In actual fact, it took a very stupid Japanese government to do Pearl Harbor. There was plenty of stuff they could pick up, cut off European colonies that had plenty of oil to keep Japan running. We would have sent some nasty grams about this, but before Pearl Harbor there was no way we would have done anything more than nasty grams about Japanese aggression. After Pearl Harbor we were mad and wanted revenge. We got it.
At the time, the United States was the most powerful country in the world. We had an educated loyal population of maybe 120 million, a continental territory, plenty of natural resources, a huge industrial base, and a Navy about as big as Japan’s. In short we were an 800 pound gorilla, and the Japanese kicked us in the teeth. Not smart.
Winston Churchill had been working his hardest to persuade the Americans to come and help him deal with Hitler. Churchill could be very persuasive, he had established a good working relationship with Roosevelt, he was well known thru his writings, but until Pearl Harbor he had not been able to talk the Americans into joining Britain in the war against Hitler. Churchill heard the news of Pearl Harbor over a regular radio broadcast. He immediately called Roosevelt, expressed his sympathies, and offered a declaration of war against Japan that very day. He ended his day convinced that the United States would get into the war against Hitler and supply the combat power needed to defeat the Nazis. Churchill wrote in The Grand Alliance “Being saturated and satiated with emotion and sensation, I went to bed and slept the sleep of the saved and thankful.”