Third and fourth terms of the presidency of Franklin D. Roosevelt
On the morning of December 7, 1941, the Japanese struck the U.S. naval base at Pearl Harbor with a surprise attack, knocking out the main American battleship fleet and killing 2,403 American servicemen and civilians. The great majority of scholars have rejected the conspiracy thesis that Roosevelt, or any other high government officials, knew in advance about the Japanese attack on Pearl Harbor. The Japanese had kept their secrets closely guarded, and while senior American officials were aware that war was imminent, they did not expect an attack on Pearl Harbor. Roosevelt had anticipated that the first attack would take place in the Dutch East Indies, Thailand, or the Philippines.
Fat Man
An estimated 35,000–40,000 people were killed outright by the bombing at Nagasaki. A total of 60,000–80,000 fatalities resulted, including from long-term health effects, the strongest of which was leukemia with an attributable risk of 46% for bomb victims. Others died later from related blast and burn injuries, and hundreds more from radiation illnesses from exposure to the bomb's initial radiation. Most of the direct deaths and injuries were among munitions or industrial workers. Mitsubishi's industrial production in the city was also severed by the attack; the dockyard would have produced at 80 percent of its full capacity within three to four months, the steel works would have required a year to get back to substantial production, the electric works would have resumed some production within two months and been back at capacity within six months, and the arms plant would have required 15 months to return to 60 to 70 percent of former capacity. The Mitsubishi-Urakami Ordnance Works was the factory that manufactured the type 91 torpedoes released in the attack on Pearl Harbor; it was destroyed in the blast.