The atomic bombings of Japan might well be one of the most important events in human history
so maybe it's no surprise that they're also one of the strangest. As plans for a nuclear attack on Japan took shape, American military planners drew up a list of
target cities. One of those cities was Kyoto. Prior to the Meiji Restoration, Kyoto had been
Japan's capital. In fact, the name literally means capital city in Japanese. For that reason
it holds a special place in the country's culture, and the city has long been famed for its beauty
and heritage. Anyone who's seen Oppenheimer will probably know where this is going
My wife and I honeymooned there. It's a magnificent city. The U.S. Secretary of War, Henry Stimson, had honeymooned in Kyoto a number of years before
the war. Having become pretty fond of the place, he took Kyoto off the target list every time it
was added, eventually taking his case to President Truman. Stimson argued that the destruction of
beautiful, historic Kyoto would only harden the Japanese people against a future American
occupation. Heck, it might even cause them to align themselves with the Soviet sphere of
influence, and you can just imagine what Truman thought of that. In the end, Stimson won out, and Kyoto was spared the destruction of the atomic bombs
Nagasaki was chosen in its place. Although that city had its own historical heritage and some significance as the heart
of Japanese Christianity this wasn enough to save it The bombs that hit Hiroshima and Nagasaki were the same in the sense that they were both nuclear weapons but they differed in a few key ways
Both bombs were detonated by forcing a mass of unstable radioactive material to go supercritical
setting off a chain reaction of shattered atoms. But Hiroshima's little boy bomb used two lumps of
refined uranium, which fired at each other like paired bullets. Nagasaki's Fat Man, meanwhile
relied on a plutonium core. This core was activated by the detonation of a spear of
conventional explosives around it. The concept of a plutonium bomb became reality at the Trinity
Test in July 1945, but uranium bombs had never been tested before the attack on Hiroshima
Scientists were very, very confident that they'd work, though, and the form of uranium required for
a working weapon was so hard to isolate that no one wanted to waste a bomb's worth of it just to
confirm what they already knew. Still, the attacks themselves became a kind of proving ground for
atomic theory. The destruction of Nagasaki proved that plutonium weapons were more devastating and
inefficient. And so most of America's subsequent nuclear weapons have followed the basic principles
of Fat Man. Nagasaki tends to be discussed less than Hiroshima, unfairly, but for understandable reasons. Even
in Japan, the news of the second atomic attack was overshadowed by the Soviet invasion of
Manchuria which had begun that same day And while it seems a little perverse to call this luck the circumstances of the bombing of Nagasaki meant that the city wasn damaged quite as badly as Hiroshima Originally the U had planned to hit the city of Kokura with the second atomic bomb On the morning of the attack though
Kokura was covered in smoke from a nearby bombing raid, and so the bombers were forced to turn
toward Nagasaki instead. But the population of Nagasaki was concentrated in two valleys cutting
outward from the city's harbor, and cloud cover on that paid old day meant that visibility was
even worse than that over Kokura. Low on fuel, and with just a single gap in the clouds they used
the bombers did what they could, dropping their payload over one of the valleys some distance
north of the city center. Even though Nagasaki's weapon was much more powerful than the one that
hit Hiroshima, the shielding effect of the terrain and the suboptimal hypocenter blunted its effect
Nevertheless, the effects of the Nagasaki bomb were devastating. There's been a lot of debate
and revision over the death toll over the years, but it's now widely believed that some 70,000
and people were killed, with a similar number injured. After Japan's surrender, the U.S. government sent a Manhattan Project physicist named Philip
Morrison to Hiroshima to survey the damage. Having witnessed the scale of the devastation
caused by the bombs, Morrison went on to campaign against the development of more nuclear weapons
Unfortunately fate had other plans Before the bombings Joseph Stalin had correctly interpreted a casual comment from Harry Truman as a reference to America nuclear program and so he leaned on his own scientists to speed up production of a Soviet bomb This project was accelerated further after the attacks on Hiroshima and Nagasaki
and the USSR successfully tested its first lightning weapon in 1949. Activists around
the world have long stressed the apocalyptic potential of nuclear weapons, arguing that
they're expensive and morally unjustifiable, to say nothing of the fact that they could destroy
humanity many times over. A number of regional treaties have banned the development of nuclear
weapons across Latin America, Africa, Southeast Asia, and the South Pacific, but nine countries
continue to operate nuclear arsenals, with weapons deployed across a further six. In total
it's thought that humanity now wields some 12,000 nuclear bombs. Now I am become death, the destroyer of worlds
The Trinity test was the first of some 500 above-ground nuclear detonations that took
place before international treaties literally forced nuclear testing underground. One of the
key consequences of these tests was the spread of carbon-14, a radioactive form of carbon that now
exists in the tissues of every living organism on Earth. Weirdly enough, there have been a few
benefits to this. Carbon-14 is useful for scientists because it decays slowly over time. This means that
by measuring the amount of carbon-14 left in a given sample, they can estimate its age. Before the advent of