Pearl Harbor and FDR

Pearl Harbor and FDR

When Franklin Delano Roosevelt addressed Congress and, via radio, the nation on the morning after the Japanese attack on Pearl Harbor and solemnly proclaimed the day of the attack—December 7, 1941—“a date which will live in infamy,” conspiracists were quick to revise the famous quotation to add “and deception.”

For well over sixty years, even the most conventionally patriotic individuals have at least wondered if the “sneak attack” on Pearl Harbor, which cost the lives of over 2,400 Americans, mostly men and women in the armed services, was really such a surprise. Even the most loyal advocates of the U.S. presidency and the most avid fans of President Roosevelt probably have asked at least once, “How much did FDR know?”

Some see Pearl Harbor as the Mother of All Conspiracies and cite such evidence as the following to support this view:

  • Since he was dealing with an isolationist nation that wanted nothing more to do with wars in Europe, FDR thought to provoke war by ordering the U.S. Navy to fire upon Nazi warships in the Atlantic. The Germans did not return fire because of Hitler’s strict orders to Admiral Erich Raeder not to engage the provocateurs.
  • FDR turned his attention toward the Japanese by initiating an embargo on war materials against Japan and threatening a blockade of Japanese shipping transporting the oil their armies so desperately needed after the campaigns in China, Korea, and Burma. To show that he meant business, FDR ordered the U.S. fleet from the West Coast to Hawaii in 1940.
  • Pearl Harbor’s resident commander, Admiral James O. Richardson, raised serious objections to the fleet move, stating that there was inadequate protection from air attack and no protection from torpedo attack. In 1932, in combined army-navy war games, 152 carrier-based aircraft caught the defenders of Pearl Harbor completely by surprise. In 1938 another carrier-borne air strike successfully “attacked” the Pacific base in an exercise. Admiral Richardson objected so strenuously to FDR’s plan that he was replaced by Admiral Husband E. Kimmel, who almost immediately upon assuming command raised the same objections.
  • By December 1940 the U.S. Army Signal Intelligence Service had broken all the Japanese codes: the “Purple Code,” utilized for all diplomatic communication; “J-19,” the main code; the “Coral Machine Cipher” or “JNA-20,” a simplified version of “Purple” used by the Japanese navy (JN); and “JN-25,” used by the Japanese fleet. The codes used by the Japanese, the bemused code breakers suggested, were little more sophisticated than the ones used by Julius Caesar. The greatest difficulty lay in transcribing written Japanese. It was revealed in 1979 by the National Security Agency that the code breakers working on JN-25 had intercepted 2,413 messages with details of the existence, objectives, and location of the Pearl Harbor Strike Force. In November and early December 1941 the code breakers worked twenty-four hours a day and spent 85 percent of their time reading Japanese navy and diplomatic messages.
  • On March 32, 1941, a navy report predicted that if Japan should ever attack the United States, they would most likely strike Pearl Harbor at dawn without warning. The U.S. fleet was the only major threat to Japan’s plans for world domination.
  • In July 1941 a U.S. military attaché at Tokyo reported secret Japanese aerial training exercises in Ariake Bay, a bay closely resembling Pearl Harbor. In that same month a U.S. military attaché in Mexico received information that the Japanese were building small submarines designed to attack the fleet in Pearl Harbor.
  • War-hawk presidential advisers, such as Secretary of the Interior Harold Ickes, continued to counsel FDR that the best way to enter the war against Nazi Germany was to declare war on Japan, one of Germany’s allies. On July 25, 1941, FDR froze all Japan’s assets in the United States, cutting off their main supply of oil. At the Atlantic Conference in August, British prime minister Winston Churchill cabled his cabinet his astonishment at how eager Roosevelt appeared to be to enter the war.


    The USS Arizona memorial marks the resting place of that battleship, which was sunk during the Japanese attack on Pearl Harbor.

  • On August 10, 1941, a British double agent known as “Tricycle” contacted the FBI and gave them exact details of the Japanese attack plans for Pearl Harbor. The FBI rejected this intelligence because it was too complete, too precise, and too detailed to be authentic.
  • In September 1941 a Korean agent informed Eric Sevareid of CBS News that the Japanese would attack Pearl Harbor before Christmas. This intelligence convinced U.S. senator Guy Gillette of its authenticity, and he personally alerted FDR, the State Department, and Army and Navy Intelligence.
  • On September 24 a coded message between Japanese naval intelligence and Japan’s consul general in Honolulu was intercepted in which the diplomat was requested to deliver the grid of the precise locations of the U.S. ships in the harbor at Pearl. The content of this message was not relayed to Pearl Harbor. Captain Alan G. Kirk, chief of Naval Intelligence, argued that there was no reason why the Japanese navy would need to know the exact grid of the U.S. fleet unless they intended to try to sink it. Because he insisted on warning Hawaii, he was removed from his position, and the message was never relayed.
  • On October 16 FDR humiliated Japan’s ambassador Kichisaburo Nomura and refused to meet with Premier Prince Konoye, a move that would allow General Tojo to claim power.
  • On November 13 the German ambassador to the United States, an anti-Nazi, told U.S. intelligence that the Japanese planned to bomb Pearl Harbor.
  • On November 25 FDR confided in Secretary of War Henry Stimson that Pearl Harbor would soon be attacked and explained that the U.S. had to maneuver the Japanese into firing the first shot in
  • order to have the full support of the American people. The president admonished his secretary of war that there must be no doubt in anyone’s mind as to who were the aggressors and who started the war.

At this date Ambassador Nomura was still conducting negotiations with Washington. Admiral Isoroku Yamamoto, commanding the Japanese attack forces as they secretly advanced into Hawaiian waters, cautioned his officers that if the negotiations in Washington should prove successful, the attack group would immediately stand down. If hostilities were declared, they would deal the U.S. fleet a mortal blow.

It is known that British intelligence decoded Yamamoto’s orders to his officers. It is suspected that Churchill sent an urgent message to FDR informing him that an attack on Pearl Harbor was imminent. If the conspiracy theorists are correct in their assumptions, the part of Yamamoto’s message that moved FDR to action were the words that the attack force would stand down if negotiations succeeded.

  • On November 26 the U.S. aircraft carriers Enterprise and Lexington were ordered out of Pearl Harbor, thus removing from the island headquarters fifty fighter planes, or 40 percent of its already scant air power. That same day, U.S. Secretary of State Cordell Hull issued the ultimatum that Japan must withdraw all forces from Indochina and China, a demand certain to antagonize the Japanese and cause them to break off negotiations.
  • On November 29 the FBI intercepted an uncoded message from Japan’s new special ambassador in Washington, Saburo Kurusu, to the Chief Foreign Officer in Tokyo in which Kurusu stated that he needed to know the “zero hour” or he would not be able to carry on diplomatic exercises. The Tokyo officer responded, “December 8 at Pearl Harbor,” which the FBI interpreted, allowing for the time difference, to be December 7.
  • On December 1 Ambassador Nomura received a cable from Foreign Minister Shigenori Togo with instructions to continue negotiations in order that the U.S. not become suspicious of Japan’s surprise attack.
  • On December 2 Yamamoto radioed the attack fleet in uncoded Japanese: “Climb Niitakayama 1208.” Niitaka was the highest mountain in Japan. U.S. intelligence could easily deduce that Yamamoto’s message called for the attack to begin on December 8 (December 7, U.S.)
  • On December 4 Elliott R. Thorpe, a U.S. military attaché stationed in Java and privy to all the messages decoded by Dutch intelligence that specified a Japanese attack on Pearl Harbor, sent four cables warning of the danger. The War Department in Washington ordered Thorpe to cease.
  • On December 5 all Japanese shipping returned to home ports.
  • On December 6, at 9:30 P.M., FDR was given the first thirteen parts of a decoded Japanese diplomatic declaration of war. After glancing through it, FDR returned to his dinner guests and announced that the war would start on the next day.
  • On December 7, at 7:55 A.M. local time, the Japanese launched a “surprise” attack on Pearl Harbor. Eighteen U.S. ships were sunk or seriously damaged, including five battleships. Of the aircraft left to defend Pearl Harbor, 188 were destroyed and 162 were damaged, most before they even managed to get into the sky. Human casualties included 2,403 dead and 1,178 wounded. Out of an attack force of thirty-one ships and 353 bombers and fighter planes, the Japanese lost twenty-nine airplanes and five midget submarines, with a total of sixty-four deaths.

It will remain for history to judge Franklin Delano Roosevelt’s actions prior to Pearl Harbor. Many researchers have reached the consensus that Pearl Harbor was not about going to war with Japan, but about entering the war with Germany.

However, one thing seems certain. Because all important Japanese codes had been broken long before Pearl Harbor by U.S. intelligence groups and the governments of Britain, the Netherlands, Australia, Peru, Korea, and the Soviet Union had warned the U.S. of the military action, the attack on Pearl Harbor was no surprise to the U.S. government.