A war today or tomorrow, if it led to nuclear war, would not be like any war in history. A full-scale nuclear exchange, lasting less than 60 minutes, with the weapons now in existence, could wipe out more than 300 million Americans, Europeans, and Russians, as well as untold numbers elsewhere. And the survivors, as Chairman Khrushchev warned the Communist Chinese, "the survivors would envy the dead." For they would inherit a world so devastated by explosions and poison and fire that today we cannot even conceive of its horrors. So let us try to turn the world away from war. Let us make the most of this opportunity, and every opportunity, to reduce tension, to slow down the perilous nuclear arms race, and to check the world's slide toward final annihilation.

A very large nuclear war would be a calamity of indescribable proportions and absolutely unpredictable consequences, with the uncertainties tending towards the worse...All-out nuclear war would mean the destruction of contemporary civilization, throw man back centuries, cause the deaths of hundreds of millions or billions of people, and, with a certain degree of probability, would cause man to be destroyed as a biological species.

Accidental nuclear war between two superpowers may or may not happen in my lifetime, but if it does, it will obviously change everything. The climate change we're currently worrying about pales in comparison with nuclear winter, where a global dust cloud blocks sunlight for years, much like when an asteroid or supervolcano caused a mass extinction in the past. The 2008 economic turmoil was of course nothing compared to the resulting global crop failures, infrastructure collapse and mass starvation, with survivors succumbing to hungry armed gangs systematically pillaging from house to house. Do I expect to see this in my lifetime? I'd give it about 30%, putting it roughly on par with my getting cancer. Yet we devote way less attention and resources to reducing the risk of nuclear disaster than we do for cancer. And whereas humanity as a whole survives even if 30% get cancer, it's less obvious to what extent our civilization would survive a nuclear Armageddon. There are concrete and straightforward steps that can be taken to slash this risk, as spelled out in numerous reports by scientific organizations, but these never become major election issues and tend to get largely ignored.

Let no one think atomic weapons are simply bigger and more destructive than other weapons; that they are just another development like the airplane or the tank. The total number of Americans killed in battle from the Revolution until tonight is a little over 526,000 people. Today a single nuclear weapon can kill more than 526,000. Our experts tell us as of today that a full-scale nuclear exchange between the East and the West would kill almost 300 million people around the world, and in the midst of that terror and tragedy we could expect that weapon after weapon would soon engulf a portion of mankind. A cloud of deadly radiation would drift and destroy, menacing every living thing on God's earth, and in those unimaginable hours unborn generations would forever be lamed.

The unacceptability of the Doomsday Machine raises awkward, unpleasant, and complicated questions that must be considered by both policy maker and technician. If it is not acceptable to risk the lives of the three billion inhabitants of the earth in order to protect ourselves from surprise attack, then how many people would we be willing to risk? I believe that both the United States and NATO would reluctantly be willing to envisage the possibility of one or two hundred million people (i.e., about five times more than World War II deaths) dying from the immediate effects, even if one does not include deferred long-term effects due to radiation, if an all-out thermonuclear war results from a failure of Type I Deterrence. With somewhat more controversy, similar numbers would apply to Type II Deterrence. (For example, some experts would concede the statement for an all-out Soviet nuclear attack on Europe, but not if the Soviets restricted themselves to the use of conventional weapons.) We are willing to live with the possibility partly because we think of it as a remote possibility. We do not expect either kind of deterrence to fail, and we do not expect the results to be that cataclysmic if deterrence does fail.

It would mean the end of civilization. As innumerable studies have shown, it would be exceptionally difficult in those circumstances to avoid escalation to total nuclear war... Humanity as such would survive in extremely poor shape. America, Russia, Europe would not.

If the President had his way, we’d have a nuclear war every week.

There have been, from time to time, changes in the degree of destructiveness of weapons and of war. These changes, until recent decades, generally have been considered not to have invalidated the precepts of Western civilization and its antecedent cultures of the moral obligation to defend its freedoms, diversity, and cultural growth from tyranny, reaction, and cultural stagnation or death. But with the advent of the nuclear age, we are faced with a change in degree that threatens to become one of kind. The destructive nature of nuclear war dictates that we no longer regard war as merely the continuation of policy by other means. The deterrence of nuclear war, until such time as technology provides a more reliable and stable method, must, for the United States, be based upon the capability to prevail if deterrence should fail. But this must be combined with an effort to join with other nations in the creation of a just international order.

Could anyone in his right mind speak seriously of any limited nuclear war? It should be quite clear that the aggressor's actions will instantly and inevitably trigger a devastating counterstroke by the other side. None but completely irresponsible people could maintain that a nuclear war may be made to follow rules adopted beforehand, with nuclear missiles exploding in a "gentlemanly manner" over strictly designated targets and sparing the population.

What has come to be called the balance of terror may seem less frightful to fanatics leading a country with a population of 600 millions. Even a war directed explicitly against centers of population may seem to it tolerable and perhaps the best means of dominating the world. Chou En-lai is reported to have told a Yugoslav diplomat that an all-out nuclear war would leave 10 million Americans, 20 million Russians, and 350 million Chinese.

Atomic war is inevitable. It will destroy half of humanity: it is going to destroy immense human riches. It is very possible. The atomic war is going to provoke a true inferno on Earth. But it will not impede Communism.

We had many contingency plans for responding to a nuclear attack. But everything would happen so fast that I wondered how much planning or reason could be applied in such a crisis. The Russians sometimes kept submarines off our East Coast with nuclear missiles that could turn the White House into a pile of radioactive rubble within six or eight minutes. Six minutes to decide how to respond to a blip on a radar scope and decide whether to unleash Armageddon! How could anyone apply reason at a time like that? There were some people in the Pentagon who thought in terms of fighting and winning a nuclear war. To me it was simple common sense: A nuclear war couldn't be won by either side. It must never be fought.

It is not even impossible to imagine that the effects of an atomic war fought with greatly perfected weapons and pushed by the utmost determination will endanger the survival of man.

War is the most terrifying example of energy directed against ourselves, and yet it was a great relief for many people throughout history. War provided them with a legitimate outlet for their aggressive feelings and an escape from their boredom. Even the humblest factory job acquired a glow of righteousness and patriotism. It is sadly significant that the number of suicides always declines during a war. A nuclear war would provide none of the satisfactions of past wars-no marching, no brass bands, no heroism. Like termites fumigated in their nests, we would all be exterminated, on any side of any curtain, by a stupendous gadget paid for by our hard-earned money and of which we were supposed to be proud. This gadget is the most powerful of all man-made transformers of energy.