The War Department had been intercepting and analyzing secret cables between Tokyo and the Japanese Embassy in Washington and thought at one point that the Japanese would attack Hawaii on Sunday, Nov. 30. A Hawaii newspaper even warned, in a blaring headline, of a possible attack.
On Dec. 4, Roosevelt received a 26-page memo marked “Confidential” from the Office of Naval Intelligence detailing Japanese espionage efforts. The possible outbreak of war is mentioned, followed shortly by this paragraph: “The focal point of the Japanese Espionage effort is the determination of the total strength of the United States. In anticipation of possible open conflict with this country, Japan is vigorously utilizing every available agency to secure military, naval and commercial information, paying particular attention to the West Coast, the Panama Canal and the Territory of Hawaii.”
These were just general warnings, however, and a huge Japanese armada was able to travel thousands of miles from Japan to Hawaii undetected. The U.S. military and government officials were caught off guard by the attack.
2. On Dec. 7, Japan attacked only Pearl Harbor.
Though the attack on Pearl Harbor was the most crippling and caused the most American losses, Japanese forces also struck the Philippines, Wake Island, Guam, Malaya, Thailand and Midway that day. In the Philippines, the capital fell to the Japanese in January 1942 and U.S. forces surrendered in May. In the Pacific, Wake Island was shelled by Japanese aircraft and ships until Dec. 11, when the Japanese attempted the first of two invasions before the island finally fell.
Guam was bombed and later invaded on Dec. 10. Malaya (now Malaysia) was invaded and fell early the following year. The invasion of Thailand lasted only a few hours before that country surrendered in December 1941. Other than Hawaii, Midway was the only target on Dec. 7 not to fall under Japanese control.
Those days were among the darkest of the Pacific war. Britain lost two huge battleships in a matter of minutesto aerial bombardment, and Winston Churchill wrote in his memoirs that their sinking was his lowest point of the entire war. The Japanese actions that day effectively crippled British naval strength in the Pacific.
3. The U.S. military responded quickly and decisively.
For months after Pearl Harbor, the United States suffered defeat after defeat in the Pacific theater. Rumors swept the country on Dec. 8 that the Navy was in pursuit of the attacking Japanese fleet, but these were false. Gen. Douglas MacArthur, in command of the Army garrison in the Philippines, sent Roosevelt a telegram pleading for naval assistance, including for U.S. subs to target the Japanese vessels delivering troops, but the requests went unanswered. There was little assistance to offer the beleaguered general, and the Philippines fell.
The first significant U.S. offensive did not come until February 1942, when the Pacific fleet began attacks on the Gilbert and Marshall islands.
Before that, the first engagement of Japanese and U.S. forces actually resulted in an American victory. Several hours before the air attack on Pearl Harbor, Japan deployed two-man submarines, or “midget subs,” against the base. The USS Ward, a destroyer on patrol outside the harbor, made first contact with a Japanese sub. It sank the vessel, resulting in two Japanese casualties and no U.S. losses.
4. Japanese Americans were the only U.S. citizens rounded up after Pearl Harbor.
Within 48 hours of the attack, more than 1,000people of Japanese, German and Italian descent, all considered “enemy aliens,” were detained by the FBI. By the end of the war, the government had interned, detained or restricted the movements of hundreds of thousands of people. Though Japanese Americans made up the majority of the roughly 120,000 people sent to internment camps, German Americans and Italian Americans were interned in Hawaii, while others were forced to move away from restricted areas on the mainland. In addition, more than 11,000 German residents of the United States were interned as well. An estimated 600,000 people of Italian descent were considered “enemy aliens” and kept under restrictions. Foreign diplomats from Germany, Japan and Italy were also rounded up and held.
The Japanese, though, were dealt with most harshly. Days after Dec. 7, Attorney General Francis Biddle ordered all Japanese Americans to surrender their cameras and broadcasting devices to local police stations. Their bank accounts were frozen, and they faced travel restrictions, among many other limitations. The FBI and the Army called for every Japanese individual to be incarcerated for the duration of the “emergency.” However, Biddle urged Roosevelt to show restraint.
5. The attack on Pearl Harbor convinced the public that the United States should enter World War II.
The attack persuaded Americans to support entering part of the war, not all of it. Before Pearl Harbor, the United States was largely isolationist, and there was almost no call to get involved in another European war. The America First movement, backed by public figures including Charles Lindbergh and Walt Disney, was growing in popularity. Its supporters had announced plans to participate in every congressional race in 1942 and support the most isolationist candidate, whether Republican or Democrat. After the attack, the America First movement came to a halt.
In the papers of Secretary of War Henry Stimson, archivists discovered a draft declaration of war against Japan, Germany and Italy for Roosevelt to deliver to Congress on Dec. 8. But that was scrapped, and FDR asked for a declaration of war against only Japan.
The attack on Pearl Harbor awoke America from its isolationist slumber and bolstered its charge into the Pacific war, but it did not spur entry into the European war. That happened when Nazi Germany and fascist Italy declared war on the United States on Dec. 11, compelling Roosevelt to respond in kind — thus committing the United States to a world war.
Craig Shirley, the president of Shirley & Banister Public Affairs, is the author of “December 1941: 31 Days That Changed America and Saved the World.”
Read more from Outlook’s Five Myths series, including:
Five myths about Newt Gingrich
Five myths about J. Edgar Hoover
Five myths about 9/11
Five myths about the American flag
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