might require 1.8 million American troops: For Operation Olympic, the invasion of Kyushu, 766,700 troops would be used; for Operation Coronet, the invasion of Honshu 1,026,000. Cited in ibid., p. 136.
“an Okinawa from one end of Japan to the other”: Quoted in ibid., p. 143.
“Now:… you’ll believe you’re in a war”: Quoted in Michael D. Pearlman, Unconditional Surrender, Demobilization, and the Atomic Bomb (Fort Leavenworth, KS: U.S. Army Command and General Staff College, Combat Studies Institute, 1996), p. 7.
“the maximum demolition of light structures”: Quoted in Stephen Walker, Shockwave: Countdown to Hiroshima (New York: Harper Perennial, 2006), p. 122.
“We should like to know whether the takeoff”: See “Letter from J. R. Oppenheimer to Lt. Col. John Landsdale, Jr., September 20, 1944,” quoted in Chuck Hansen, The Swords of Armageddon, vol. 7 (Sunnyvale, CA: Chucklea Publications, 2007), p. 30.
the president’s Target Committee decided: See “Memorandum for: General L. R. Groves, Subject: Summary of Target Committee Meetings on 10 May and 11 May 1945,” May 12, 1945 (TOP SECRET/declassified), reproduced in Merrill, Documentary History of Truman Presidency, pp. 5–14.
“No suitable jettisoning ground… has been found”: Ibid., p. 9.
try to remove the cordite charges from the bomb midair: Ibid.
“bomb commander and weaponeer”: See Craven and Cate, Army Air Forces in World War II, p. 716.
“a less than optimal performance”: Quoted in Martin J. Sherwin, A World Destroyed: Hiroshima and Its Legacies (Stanford, CA: Stanford University Press, 2003), p. 231.
Parsons and… Morris Jeppson, left the cockpit: See Walker, Shockwave, pp. 213–17.
leaving about three hundred thousand people in town: The estimates range from 245,423 to 370,000. See Frank, Downfall, p. 285.
the temperature reached perhaps 10,000 degrees Fahrenheit: Estimates of the heat ranged from 3,000 to 9,000 degrees Centigrade—5,432 to 16,232 degrees Fahrenheit. Cited in “The Effects of Atomic Bombs on Hiroshima and Nagasaki,” U.S. Strategic Bombing Survey, June 19, 1946, pp. 31–32.
a roiling, bubbling sea of black smoke: The physicist Harold Agnew, who rode in a plane following the Enola Gay, described the blast to me. Agnew filmed the mushroom cloud as it rose into the air and captured the only moving images of the explosion.
98.62 percent of the uranium in Little Boy was blown apart: Interview with Bob Peurifoy.
Only 1.38 percent actually fissioned: Ibid.
eighty thousand people were killed in Hiroshima: According to a study conducted by the U.S. Strategic Bombing Survey right after the destruction of Hiroshima and Nagasaki, the “exact number of dead and injured will never be known because of the confusion after the explosions.” The study estimated the dead at Hiroshima to be between 70,000 and 80,000. According to the historian Richard Frank, the police department in Hiroshima prefecture estimated the number to be about 78,000. Many thousands more died in the months and years that followed. See “The Effects of Atomic Bombs,” p. 15; and Frank, Downfall, pp. 285–87.
more than two thirds of the buildings were destroyed: According to Japanese estimates, 62,000 of the 90,000 buildings in Hiroshima were destroyed, about 69 percent. Another 6.6 percent were badly damaged. Cited in “Effects of Atomic Bombs,” p. 9.
0.7 gram of uranium-235 was turned into pure energy: Albert Einstein’s equation for converting the mass of an object into an equivalent amount of energy helps to explain why something so small can produce an explosion so large. The energy that can be released, Einstein found, equals the mass of an object multiplied by the speed of light, squared. Since the speed of light is more than 186,000 miles per second, the equation easily produces enormous sums. The estimate of 0.7 grams is based on the quantity of uranium-235 in Little Boy and an assumption that the bomb’s yield was 15 kilotons. The power of even a rudimentary nuclear weapon is difficult to convey. The city of Hiroshima was destroyed by an amount of uranium-235 about the size of a peppercorn or a single BB. I am grateful to Bob Peurifoy for helping me to understand the relationship between a nuclear weapon’s potential yield and its efficiency.
A dollar bill weighs more: According to the Federal Reserve, a dollar bill weighs 1 gram.
“the basic power of the universe”: See “President Truman’s Statement on the Bombing of Hiroshima, August 6, 1945,” reproduced in Kort, Columbia Guide to Hiroshima, p. 230.
“We are now prepared to obliterate more rapidly”: Ibid., p. 231.
“an aroused fighting spirit to exterminate”: Quoted in “Effects of Atomic Bombs,” p. 8.
