It was 69 years ago today that the Empire of Japan launched what President Franklin Roosevelt called that "unprovoked and dastardly attack" upon the United States at Pearl Harbor, Hawaii to bring the country militarily into World War II. FDR had it right; it was dastardly, and by all accounts, unprovoked. That doesn't mean it wasn't unexpected; after all, the U.S. and Japan had been on the outs for quite awhile, especially with the attempted Japanese conquest of China and Japan's signing a few years earlier of the Tripartite Pact with Nazi Germany and Fascist Italy the year before. But as FDR mentioned in his speech before Congress the next day, Japan did not indicate that they had declared war on the United States, making the attack upon Pearl Harbor even more egregious.
In the late fall of 1941, war was being waged primarily in the Soviet Union, northern Africa, and in China; all of Europe save Great Britain and the Soviet Union (and the neutral countries: Sweden, Switzerland, Spain, Portugal, and Ireland) had been conquered by the Nazis. While the fighting was fierce everywhere, the big action was taking place in the Soviet Union as the Nazis were pressing forward towards Moscow. The Russians had taken huge losses (around 4 million) in fighting back against the Germans, but had to keep retreating in the face of the Nazi onslaught. At the same time, the Soviets had large numbers of troops in the east in the event of a Japanese attack; the Russians had whipped the Japanese in a major battle in 1939 during a border dispute. Stalin's super-spy in Tokyo, Richard Sorge, had informed his boss that the Japanese had set their sights south and east and that no Japanese attack was forthcoming. This allowed Stalin to move 40 divisions out of that sector to be used to defend Moscow; on December 6, the Soviets counterattacked and stopped the Nazi advance.
The Japanese had decided that they were going to make a move upon Southeast Asia. But to do that, they needed to strike at the United States to knock them out of the war before they really got into it. The plan was to not only knock out all the capital ships (battleships) that were stationed at Pearl Harbor; but the main goal of Admiral Isoroku Yamamoto's plan was to take out the American aircraft carriers. This would keep the Americans from using them to launch air raids on the Imperial Navy and newly won Japanese territory.
In utter secrecy and in complete radio silence, the Japanese fleet left Tokyo in late November intending to attack Pearl Harbor on December 7, shortly after the government of Japan had relayed its intentions to the United States. There were also some small submarines patrolling to keep track of the U.S. Navy's vessels. While the submarines had been detected and sunk, which should have alerted Pearl Harbor's commanders that something was afoot, the Japanese attack proceeded pretty much without a hitch. All eight battleships moored at the base were sunk or damaged, although all but the U.S.S. Arizona (pictured above) and the U.S.S. Oklahoma returned to duty after repairs. Aircraft stationed nearby were hammered by the Japanese assault. Around 2500 Americans had been killed, nearly half of them dying in the Arizona. On the same day as the Pearl Harbor attack, the Japanese assaulted Southeast Asia and many of the islands in the Pacific, especially the Philippines. Three days after Pearl Harbor, the Japanese had sunk two of the British capital ships that were instrumental in sinking the German battleship Bismark several months earlier, the battleship H.M.S. Prince of Wales and the battlecruiser H.M.S. Repulse.
Yet, there had been no official declaration of war from Japan prior to the attack. In the eyes of the Roosevelt administration and the federal government, what the Japanese had done was both "unprovoked" and "dastardly". Immediately, the FDR propaganda machine went into high gear to get all they could out of America to defeat this enemy, as well as the Germans and Italians who had declared war on the U.S. within a few days of Pearl Harbor. While it isn't clear he said it, the quote attributed to Admiral Yamamoto, "I fear that all we have done is to awaken a sleeping giant and fill him with a terrible resolve," was quite prescient.
Worse for the admiral and the Imperial Navy, the American aircraft carriers were not at the base in Pearl Harbor the morning of December 7. While nothing could stop many of the conquests by the Japanese, including in the Philippines, within seven months those American carriers would prevent an invasion of part of New Guinea, transport B-25 Mitchell aircraft to bomb Tokyo, and sink four of the six Japanese carriers that had been used for the Pearl Harbor attack. The "sleeping giant" had not been knocked out of the war, and was most definitely filled with a "terrible resolve". While the plan to attack the U.S. at Pearl Harbor was bold and executed brilliantly, it was, in the end, a huge and bloody blunder that would be felt by the Japanese people in the next few years.