Pearl Harbor and September 11th - a Comparison

Over the long course of American history, never has there been a more surprising display of aggression against the United States than the attacks on Pearl Harbor and those of 11 September 2001. Both attacks were meticulously planned, caught the American government, military, and citizens completely off guard, and caused the United States to reply with extreme violence. However, despite the amount of similarities that can be found between the two events, the two are very different. Japan's attack was a military-planned direct attack on America's armed forces, and stemmed from the Empire's problem with the American support of China while Japan was attempting to colonize the Chinese. On the other hand, the attacks on 11 September 2001 were planned by a terrorist organization with no national backing on civilians for the most part, and stemmed from the fundamental Muslim's extreme dissent of the American way of life. Whether historical analysis of the two events aims to find similarities or differences, there is much that can be learned from these attacks. The idea that United States defenses can be breached, as long as there is an exhaustive and flawless plan put into action is shown in both, as long with the necessity for all intelligence to be shared among government and military bodies is evident. However the most glaring discovery made when analyzing Pearl Harbor and 11 September 2001 is that no matter how much intelligence exists, it is essentially impossible to predict where and when a surprise attack will take place.

Pearl Harbor has long been a topic of debate among historians and there are a number of key questions that historians come back to again and again. How much military intelligence was available to military and political leaders? Was intelligence mishandled? Even if there was no way to know that Japan was about to mount a surprise attack on Pearl Harbor, why were those in charge at the base in Pearl Harbor not prepared to defend the base given the fact that there was an ongoing war? There are a few sources that help to understand the key historical questions surrounding the attack on Pearl Harbor.

In 1991, David Khan published an article in Foreign Affairs entitled, "The Intelligence Failure of Pearl Harbor." Khan is both a historian and a cryptologist and incredibly adept regarding American military intelligence. Khan believes that Americans were caught off guard at Pearl Harbor due to an intelligence failure. Specifically, we failed to gather the intelligence necessary to prevent an attack from Japan. Khan believes that this is information that we couldn't have gathered since Japan "has sealed all possible leaks." With his expertise being in the field of cryptology, Khan put a great deal of focus on American code breaking and the information that was able to be discovered by Americans about the Empire of Japan before the attack on Pearl Harbor. The first Japanese code breaking machine produced by Americans was called "RED," but once that machine became obsolete it was time for a change. "Faced with the loss of the nation's paramount intelligence, the Signal Intelligence Service mounted a concentrated attack on Japan's new machine...Americans called the new machine 'PURPLE'."

Though the "PURPLE" machine was able to intercept diplomatic messages between Japanese leaders and their diplomats all over the world, it could not decode Japanese military or naval messages simply due to the fact that Japan did not transmit those messages by radio. However this did not mean that there was no intelligence available to the United States. "In January 1941 Ambassador Joseph Crew duly noted that a Peruvian colleague had heard that Japan was planning an attack on Pearl Harbor. The rumor was false, for at the time no attack was being planned. Washington [D.C.], in any event, filed the report and forgot about it." Based on intelligence that was received as well as primary sources from the United States at the time of Pearl Harbor, Khan concludes that the United States Government, along with Americans, did not think Japan had the nerve to attack America on their own soil. The United States assumed that they would eventually be at war with Japan, but were not able to believe that it would be an attack at home that would bring them into the war.

In the fall of 1941, the conflict between the United States and the Empire of Japan continued to grow. Japan moved further into French Indochina, despite numerous warnings from the United States that they were opposed to the invasion. As Khan details, there were numerous other intercepts and small signs that the chance of war was increasing, but it was not until January 6, 1941 that President Roosevelt was shown an intercepted message from Japan that caused him to react by saying "This means war." This was mere hours before the attack--six Japanese aircraft carriers were already in the seas north of Hawaii.

Although the title of Khan's article is "intelligence failure," it is more accurate to say that he believes the attack on Pearl Harbor was more of an intelligence success