Over the last few years I’ve been slowly growing a thesis that the most important truths in a given society are those which are so important that not only does nobody do or say or think about them, but nobody is even aware of them — the truths which are buried so deep beneath layers of denial as to bear comparison with something like Jungian racial memories.
The most important date in human history by far was July 16, 1945. There isn’t even any also-run to compare with it; that date stands alone like Olympus Mons on an infinite plain. Yet how many people today can even identify that date?
Human survival for the last ten million years has rested solely on one weak reed: That humanity’s best efforts to exterminate itself and to destroy the resources upon which it depends for survival have always been defeated by sheer inability to do the job — that humanity always survived in the end thanks to the Angel of Impotence swooping in at the last moment to save it.
On July 16, 1945 that weak reed broke.
The bright light of the first artificial dawn illuminated a stark choice: Either humanity eradicated war, or war eradicated humanity.
Without a vote, without any discussion, without any announcement, humanity with a single vast shared understanding agreed that war was just too jolly to give up.
On that day, humanity drove off a cliff at top speed, waving cheerily, and everything since then has been just waiting for the impact at the bottom of the cliff.
While pulling layer after layer after layer of denial over that decision and that consequence. Whee! Are we having fun yet?
The real significance of nuclear power, which nobody dare ever think about, much less mention, is that nuclear weapons and nuclear power plants make the military perfect storm. They go together like love and marriage, like a horse and carriage, like the two components of a binary nerve gas.
The problem with nuclear weapons is that they just have a few pounds of radioactives. As Hiroshima and Nagasaki demonstrated, you get a little bang, everything and everyone in a hundred square miles or so get vaporized, and then you rebuild. No muss, no fuss. Not much different from Xerxes sacking Athens in 480 BC.
Conversely, the problem with nuclear power plants is that they just don’t have the peak power output to effectively spread their radioactives. As Chernobyl demonstrated, the core just melts down into a puddle, a few kilograms of radioactives escape, you put a fence around a few thousand square miles of land for a few centuries, and life goes on. No muss, no fuss. We destroy more land than that every year via abusive agriculture and desertification. Yawn.
But a nuclear weapon targeted on a nuclear power plant — sublime beauty!
A nuclear power plant together with its associated fuel dumps can contain thousands of tonnes of radioactives — and one little teeny A-bomb, the kind so small and harmless that the SALT treaties don’t even bother mentioning much less counting them — one negligible backpack or artillery shell nuke is quite sufficient to vaporize those thousands of tons of radioactives, allowing them to settle out downwind for tens of thousands of miles and get efficiently incorporated into the food chain, thereafter to concentrate steadily until reaching top predators like tuna, eagles — and humans.
Scientific American once ran an article showing that one nuke on one midwestern nuclear powerplant would be sufficient — given normal prevailing winds — to take out essentially the entire East Coast of North America. (Try that with a coal plant!)
But we’re not going to be talking about just one nuclear power plant entering the stratosphere via mushroom cloud. When the killing frenzy hits, the first thing humans do is to blow up every factory and power plant in sight. The first thing the Americans did in the Korean War was to blow up the biggest dam in the country, with loss of civilian life fully comparable to Dresden, Hiroshima or Nagasaki. The US has over one hundred civilian nuclear targets (um, “reactors”) sitting waiting to play their final roles. The fallout plumes from all of them combined color the Northern Hemisphere dead black.
(Then comes nuclear winter — ten years of no crops on a planet with a two-month supply of food. What fun! There’s nothing quite like freezing to death while starving for lack of radioactive food. Looking on the bright side, very few people will live long enough to come down with cancers — count your blessings! But I digress.)
Beyond that, there are dozens to hundreds of reactors specifically designated to be blown up in case of war: No major modern warship is complete without a nuclear reactor, and warships exist specifically to blow each other up — that is their exact design purpose. So blowing up nuclear reactors is firmly established as a central focus of the next developed-nations war.
By common consent, the nuclear-powered aircraft carriers will be the first to go; they are sitting ducks for modern torpedos and missiles. Modern submariners insist that there are only two kinds of warships: submarines and targets.
To what shall we equate one destroyed nuclear aircraft carrier? A hundred Chernobyls? A thousand? A million? After all, Chernobyl was on land and the molten core buried itself in the local bedrock, after which a heroic cast of thousands assembled a concrete sarcophagus. A nuclear aircraft carrier blown to bits will be dumping its reactor core into the ocean, not into rock, and nobody is going to be building any kind of containment structure around the wreck in the middle of a war as it sits glowing and boiling satanically on the seabed.
Once the aircraft carriers have been eliminated, the real fun starts: the patient, silent game of nuclear-powered hunter-killer attack submarines stalking and killing other nuclear-powered submarines — both attack and ballistic-missile.
The aircraft carriers will likely get taken out by conventional weapons, since they will go at the start of the war when tempers are cool and everyone is still having a good time and respecting the Laws of War and such. But common sense suggests and war games conclude that as the war progresses and at least one side starts feeling desperate that gloves come off and the the nuclear weapons come out of the box; it is a good guess that the last few nuclear submarines taken out will be vaporized by tactical nuclear weapons, not merely blown up by conventional explosives. Their tons of radioactives, thus, including any hoarded MIRVed ICBMs, will be injected into the stratosphere for all to enjoy within days, rather than spread over the seabed to enter the foodchain over months, decades and centuries.
(Archaeologists already use the global radioactives layer from the 1960s as a standard dating horizon; any intelligences active on Earth millenia from now will find the World War III horizon an even better reference.)
(By the way, wars end when one power is no longer able to participate — when the war machine crumbles. In the past, the war machine was built of humans, and by rule of thumb became inoperative when casualities reached about ten percent. For example, in World War II German resistance collapsed after losing about six million from a population of about seventy million . With robotics, however, we may soon reach a point at which it is possible for a country to continue warring even after the loss of essentially the entire population exclusive of military leaders in bunkers. That would add an extra piquancy to war missing in previous eras — losing countries would be extirpated as completely as Sybaris. Should some scattered humans survive WW III, perhaps “America” will replace “Sybaris” as the word for glory and luxury lost without trace.)
What’s that you say? Nukes have made nuclear war unthinkable?
Funny you should say that. Alfred Nobel said the same thing about dynamite: He felt no guilt about selling high-explosive based weapons all over the world because they made war too terrible for any sane leader to contemplate.
Maybe so, but the Great War arrived on schedule all the same, and then had to be renamed World War I to make room for the sequel.
Lewis Richardson demonstrated in a classic paper in 1948  that interstate conflicts obey a power law: For each increase of x10 in fatalities, the number of wars decreases by x2.5, along a nice smooth curve. (Nobody has a good theory explaining this.)
What does this tell us?
It tells us that local wars and big wars and world wars are not different phenomena. They are all the same thing. A world war is just a local war that got out of hand. Sometimes you shoot a Serbian Archduke and nothing happens. Sometimes you shoot a Serbian Archduke and you get a pleasant little Balkan war where only expendable Serbs and Croats and such die while everyone else tut-tuts. And sometimes you get a world war where people you know and love die. By the billion. You just never know.
You say our survival for half a century on a planet groaning under uncounted (literally) tens of thousands of nuclear weapons demonstrates that we would never actually use them?
Actually, the history of the era demonstrates quite the opposite; that we’ve survived to date through sheer dumb luck. If Krushchev had been as belligerent as JFK, you’d be dead now. On well over a dozen known occasions (and how many unknown ones?) the world teetered on the very brink of accidentally initiated thermonuclear war  — just about everyone alive today owes their lives to various unsung heroes who at the crucial moment disobeyed orders and prevented armageddon. In a rational world they’d be world celebrities with statues in front of the UN. In a world order focussed on denial, they are persecuted nonentities — traitors who dared derail destiny. (Can you name a single one of them?)
You say American early warning systems are now far too comprehensive to allow accidental nuclear war? You don’t get it. Recent studies show roughly 200 weapons are sufficient to trigger nuclear winter. Russia and the United States may wind up not being involved in WW III at all. North Korea and China could do it themselves without American involvement. Or France and South Africa. Or Israel and Iran. Or India and Pakistan. Are you sure Pakistan’s nuclear early warning system will work with perfection throughout a civil war? And those of every other nuclear power? Forever? As steadily more countries join the nuclear club each decade, having seen both Iraq and Libya obliterated for the crime of failing to have a credible nuclear deterrent?
Humanity faces only one significant problem today.
Yet nobody you know even recognizes July 16, 1945.
Have a nice day.
 Richardson, Lewis F. 1948.
Variation of the frequency of fatal quarrels with magnitude.
Journal of the American Statistical Association 43 (244) 523-46.