Seventy-five years ago, on August 6, 1945, the world exploded into a new era. A single B-29 Superfortress plane, nicknamed Enola Gay, launched a new type of weapon – an atomic bomb – on the Japanese city of Hiroshima. Releasing the explosive power of 12,500 tons of TNT, the heat of the sun and a cloud of mushroom radiation, it destroyed 5 square miles of the city and killed 150,000 people, half of which instantly. Together with a second atomic bomb dropped on Nagasaki three days later, he forced the Japanese to surrender, ending the Second World War. But it also triggered a nuclear arms race that continues today; and while the possession of entire arsenals of these weapons in the hands of nine nations may have deterred political leaders from starting some wars, it is also true that if these bombs – most of them dozens or hundreds of times more powerful than that dropped on Hiroshima – never used in anger again, the consequences could be catastrophic, possibly resulting in a “nuclear winter” that puts an end to most life on Earth.
And so, on the anniversaries of Hiroshima, as a variant of the day of the universal judgment of the Jewish Passover, we ask the four questions that ethics and historians have been asking for decades:
• Why did President Harry Truman decide to bomb Hiroshima?
• Why then did you decide to bomb Nagasaki?
• Would a demonstration of the weapon – a massive eyewitness explosion in the middle of nowhere – convince the Japanese to surrender?
• How could the war have ended – more or less people would have died – if the atomic bomb had never been invented?
On the first two questions, the declassified archival documents are clear enough: there has never been a decision to drop either bombs. Instead, there was a decision build an atomic bomb. Once ready, it was used; once the second bomb was ready, it was also used. From the beginning, this was the plan: an automatic sequence from building the bomb to the test to drop it on the enemy. The only decision Truman made was not to change the plan.
The bomb-building project began with a 1939 letter from Albert Einstein to President Franklin D. Roosevelt, confident that a uranium fission chain reaction could produce a very powerful bomb and warning that German scientists were working on building one for the Nazi government. Two years later, Roosevelt set in motion the Manhattan Project, a $ 2 billion secret enterprise run by the nation’s best physicists and engineers, under the supervision of General Leslie Groves. When they detonated the first bomb on the Trinity Test site in New Mexico on July 16, 1945, the Germans had surrendered. And so, it would have been used against the Japanese, who were fighting fiercely.
Already, at that point, the War Department had created a target panel, to decide exactly where to drop the bomb. In the minutes of a meeting of May 1945 it is noted that the destruction of the selected target should cause “the greatest psychological effect against Japan”. With this measure, “Hiroshima has the advantage of being of such size, and with the possible concentration from the nearby mountains, that a large part of the city could be destroyed”.
Scott Sagan, a nuclear scientist at Stanford University, recently claimed that deliberately dropping the bomb on a city, with the primary intention of killing civilians, would be considered a war crime, a violation of the Geneva Convention, which was not still signed in 1945. Still, well before the Second World War, distinctions had been drawn between civilian and military targets, particularly in the context of the aerial bombardment, which started in the First World War.
The only decision made by Truman was not to change the Plan.
However, this Rubicon was firmly crossed by the time of Hiroshima. At the beginning of the Second World War, the allied air forces pursued a “precision bombing” policy against the “vital nerve centers” of the German economy. But that meant flying in daylight, in order to see the target, which opened the bombers to German fighter pilots and anti-aircraft gunners. The Allies instead began to fly at night, but they could not find specific targets, so they made a necessity and proclaimed that the main target of the attack was the “morale” of the German people: it didn’t matter what I hit for a long time while you hit something . Almost a fifth of German houses were destroyed or severely damaged by Allied bombing, 300,000 civilians were killed and 780,000 injured. Similarly, Germany launched its V1 and V2 rockets in the heart of London, according to the same logic.
Within the last year of the war, in the Pacific, the 21 year old of General Curtis LeMayst The Bombers Command set fire to Tokyo and almost all other cities in Japan. (When the Target Committee decided which cities to hit with A-bombs, they skipped over the remaining cities that LeMay still had plans to incinerate.) In March, LeMay piled 334 B-29s to launch incendiary bombs on Tokyo, killing 84,000 residents . The only thing about the atomic bomb was that it killed many civilians; was that he did it with extraordinary efficiency, since, as the targeting panel said, “the greatest psychological effect”.
In June 1945, some of the Manhattan Project physicists, in particular James Franck and Leo Szilard, expressed concern about what they called the bomb’s “political and social problems”: its murderous destructiveness and the possibility of a nuclear arms race after the war. – and urged the administration to demonstrate the bomb, on a “deserted or barren island”, before using it to kill people. A month later, they and 66 of their colleagues signed a petition to the president, pointing out the same points. However, the project’s top scientists – including J. Robert Oppenheimer, Ernest Lawrence, Enrico Fermi and Arthur Compton (who was the immediate supervisor of Franck and Szilard) – agreed, saying that a peaceful demonstration would prolong the war . The best US officials sided with the directors or, more precisely, took the directors’ reports as an affirmation of their position. President Harry Truman – who had not heard of the Manhattan Project until April when Roosevelt died and stepped forward from the vice president to the commander in chief – never saw these petitions. (After the war, many of these scientists joined or led anti-nuclear organizations. Oppenheimer opposed the development of the much more powerful hydrogen bomb and consequently lost his security clearance.)
Before the bombs fell, Truman’s kidnappers told him that Hiroshima and Nagasaki were military targets. (There was a troop loading dock on the outskirts of Hiroshima, but this was a minor consideration; the bomb was aimed at the city center.) For many years Truman pretended to feel totally comfortable after dropping the bombs, bragging about “I never lost sleep” on Hiroshima or Nagasaki. However, the archives reveal that he was actually horrified by the civil destruction – and even ordered his generals not to drop a third bomb, so he shouldn’t have killed more of “those children.” Groves, the supervisor of the Manhattan Project, intended to do it as soon as a third bomb was ready, shortly after August 24, if Japan hadn’t surrendered since then; but the chief of staff of the Army, General George Marshall, told him not to do so without Truman’s express orders. (Not long after the war, Truman imposed civilian control over atomic weapons, saying to his generals, “This is not a weapon military”; for a few years, A-bombs were kept separate from the planes that would transport and drop them, under the control of the Atomic Energy Commission, not the strategic air command.)
So Truman decided not to use a third bomb. Could he decide not to use the second bomb or the first bomb? Would Roosevelt, who knew all the secrets of the bomb, stop the juggernaut before destroying Hiroshima? Probably not.
The archives show that senior officials have belittled the idea of a peaceful demonstration proposed by Franck, Szilard and others. However, officials rejected the idea.
First, they said, the bomb could be a disaster, in which case a demonstration would be counterproductive; could convince the Japanese to fight without fear of any weapon. Although the next bomb – the bomb that hit Japan – exploded with great intensity, they could see its success as a fluke.
Second, most senior officials at that time had dropped any resistance once they had the idea of killing large numbers of civilians for a “psychological” impact. Giving the Japanese any kind of warning, let alone a demonstration, would have dampened the surprise and therefore its impact.
The archives reveal Japanese cable traffic – which the Americans had decoded – suggesting a possible readiness to surrender even before the bombs fell. US officials have followed these suggestions, but, as other documents show, they have not led anywhere. Certainly some Japanese officials and many people were tired of the war, but the best military officers, who actually ran the government, were willing to fight – and thought they could defeat the Allies once they hit the Japanese mainland. In fact, they surrendered, even after the atomic bombings, only when Emperor Hirohito nullified Japan’s official powers, invoking his divine status in one go, avoiding normal procedures. If he hadn’t, the military could have fought.
After the war, reports claimed that 250,000 US troops would die in the invasion of Japan, which was scheduled for August. In fact, at the time, the estimate was 31,000. However, many soldiers are dead. After four years of deadly fighting, especially in the midst of the brutal war in the Pacific, no president would have decided not to launch an extremely powerful bomb – a bomb that, moreover, had been built at high costs – if the possibility existed that it could pose end of the war and therefore prevent the need for an invasion.
Few Americans in a position of power were meditating on the long-term implications of the bomb.
At least one senior U.S. official saw a side benefit to the bomb. In May 1945, Secretary of War Henry Stimson told his assistant secretary, John McCloy, that possession of the bomb could have given the huge US leverage – “a royal flush” – over the Soviet Union in the next post-war competition. , which many were seeing as inevitable. Truman was traveling to the Potsdam Conference to discuss the end of the war and the post-war Europe division with Josef Stalin and Winston Churchill when the Trinity test took place. He told Stalin that his scientists had tested a weapon. Stalin did not seem impressed, only replying that he hoped it would force Japan to surrender. Stalin obviously already knew about the Manhattan Project, thanks to some Soviet spies on the scene. Two days after Hiroshima, Soviet troops invaded Japan through Manchuria, as Stalin had agreed to do, although the bomb drop increased his program by several days, so that he could take part in the victory and territory. Some Japanese officials had contacted Moscow to help them end the war on good terms. Hiroshima’s sequence, then Stalin’s invasion, then Nagasaki canceled those hopes.
In any case, the bomb did not give the United States any obvious advantage in the early years of the cold war, when the Soviets occupied all of Eastern Europe and tried to move Italy, Greece and Turkey. In 1949, the Soviets built and tested their atomic bomb. The result was an arms race, which within a decade settled in an excessive stalemate, in which neither side would “win” a nuclear war, regardless of who fired first.
In the three weeks between Trinity and Hiroshima, few Americans in positions of power were meditating on the long-term implications of the bomb, nor did they have much basis for doing so. Outside the small group of physicists working on the project, nobody understood how powerful this new weapon was; the horror of radioactive fallout was even less completely absorbed. The aftermath of the bomb on future war and peace issues – “political and social problems,” as Franck and Szilard said – took the place of the understandably urgent task of winning the current war before tens of thousands of other American troops were dispatched to their destinies.
War revolutions often come when short-term priorities prevail over futuristic philosophy. After the 2010 cyber attack known as Stuxnet, in which the United States and Israel jointly sabotaged the centrifuges in the Iranian reactor in Natanz, delaying the country’s nuclear program by a few years, General Michael Hayden, former director of the CIA and Retired NSA compared the attack on Hiroshima. “I don’t want to pretend it’s the same effect,” he told the New York Times David Sanger, acknowledging that the atomic bomb was obviously much more destructive, “but at least in a way, it’s August 1945.”
He continued: “Previous cyber attacks had effects limited to other computers.” Stuxnet, however, was “the first major attack” that caused “physical destruction”. Hayden supported the attack, saying “I think destroying a cascade of Iranian centrifuges is an unbound asset.” Even so, he cautioned, “Someone crossed the Rubicon. Now we have a legion across the river.”
Something had changed in the nature and calculation of the war. Not long afterwards, in retaliation, Iran launched a cyber attack against Aramco, the US-Saudi Arabia oil company, wiping out all its hard drivers. North Korea launched a cyber attack on Sony Pictures, avenging the release of a film in the studio that teases – and depicts the assassination of – its leader, Kim Jong-un. More than 20 countries now have cyberunits within their military. We do not yet know whether this will transform the nature of the war or simply expand its terrain.
The officials and officers who set the Manhattan Project in motion and did nothing to stop it, did not even know what its final impact would be, until its terrible effects were used and recorded. Even then, for many years later, the officers in charge of the war plans represented the atomic bomb – and therefore the hydrogen bomb – as ordinary weapons, written in large letters. Until the 1970s, nuclear weapons remained the centerpiece of those war plans.
This is no longer true, but even so, the officers of the United States Strategic Command and various civilian strategists in the Pentagon and various think tanks are looking for new ways to design “smaller” nuclear weapons (that is, only one slightly less powerful than the Hiroshima bomb) and more “versatile”, to make them more “usable” in a conflict that gets out of hand. A new era was born in August 1945, and we are still living there, with no visible way out.
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