Global catastrophic risk

"Right now we are facing a man-made disaster of global scale, our greatest threat in thousands of years: climate change. If we don’t take action, the collapse of our civilisations and the extinction of much of the natural world is on the horizon."

"A war with Russia or China would risk escalating into World War III. As Andrew Weiss told the Times on Ukraine, Russia and China would have conventional “escalation dominance,” as well as simply more at stake in wars on their own borders than the United States does. So what would the United States do if it were losing a major war with Russia or China? U.S. nuclear weapons policy has always kept a “first strike” option open in case of precisely this scenario. 'The current U.S. $1.7 trillion plan for a whole range of new nuclear weapons therefore seems to be a response to the reality that the United States cannot expect to defeat Russia and China in conventional wars on their own borders... there can be no winner in a war that kills everybody. Any use of nuclear weapons would quickly trigger a massive use of them by one side or the other, and the war would soon be over for all of us."

"There are clear and predictable consequences for the world if human beings continue to rape the earth and plunder its resources; to exploit, oppress, and dominate the weak and the poor for the sake of greed and the hunger for power; to depend on ever-rising levels of violence and ever more lethal instruments of death and destruction in order to secure positions of power and privilege."

"We have men of science, too few men of God. We have grasped the mystery of the atom and rejected the Sermon on the Mount. The world has achieved brilliance without conscience. Ours is a world of nuclear giants and ethical infants. We know more about war than we know about peace, more about killing than we know about living. If we continue to develop our technology without wisdom or prudence, our servant may prove to be our executioner."

"The American, English and French newspapers are spewing out elegant dissertations on the atomic bomb. We can sum it up in a single phrase: mechanized civilization has just achieved the last degree of savagery."

"As previous work has pointed out, the nuking of a sufficiently large city would be enough to generate a global-scale nuclear autumn. Take Los Angeles, for example, a city that extends for 500 square miles. The explosion and resulting fires would send an estimated 5.5 million tons of ash and soot into the stratosphere, causing sunlight, temperatures, and rainfall to temporarily decrease around the world. Globally, this would result in diminished growing seasons for the next half-decade, and temperatures would be the lowest in a thousand years. In some parts of the world, rainfall would be down by as much as 80 percent. But unlike this earlier work, which focused on relatively small, 15-kiloton nukes exploding over cities, the new study looked at whether today’s more powerful weapons could trigger nuclear autumn all on their own. They can. Liska and his colleagues found that the US, Russia, and China all have weapons that could trigger a nuclear autumn through the detonation of fewer than five bombs."

"Today the atomic bomb has altered profoundly the nature of the world as we know it, and the human race consequently finds itself in a new habitat to which it must adapt its thinking."

"Nuclear proliferation is on the rise. Equipment, material and training were once largely inaccessible. Today, however, there is a sophisticated worldwide network that can deliver systems for producing material usable in weapons. The demand clearly exists: countries remain interested in the illicit acquisition of weapons of mass destruction. If we sit idly by, this trend will continue. Countries that perceive themselves to be vulnerable can be expected to try to redress that vulnerability — and in some cases they will pursue clandestine weapons programs. The supply network will grow, making it easier to acquire nuclear weapon expertise and materials. Eventually, inevitably, terrorists will gain access to such materials and technology, if not actual weapons. If the world does not change course, we risk self-destruction."

"The modernization and expansion of nuclear arsenals in multiple countries, combined with the lack of diplomatic efforts to reduce nuclear risks, have increased the likelihood of catastrophe. Development of hypersonic glide vehicles, ballistic missile defenses, and weapons-delivery systems that can use conventional or nuclear warheads raise the probability of miscalculation during a crisis. By our estimation, the potential for the world to stumble into nuclear war—an ever-present danger over the last 75 years—increased in 2020."

"As long as weapons of mass destruction exist, primarily nuclear weapons, the danger is colossal. All nations should declare... that nuclear weapons must be destroyed. This is to save ourselves and our planet."

"Anyone who thinks we can continue to have world wars but make them nice polite affairs by outlawing this weapon or that should meditate upon the outlawing of the cross-bow by Papal authority. Setting up the machinery for international law and order must surely precede disarmament. The Wild West did not abandon its shooting irons till after sheriffs and courts were established."

"I regard the employment of the atom bomb for the wholesale destruction of men, women and children as the most diabolical use of science."

"Climate change is the defining issue of our time – and we are at a defining moment. We face a direct existential threat."

"The use of the atomic bomb with its indiscriminate killing of women and children, revolts my soul."

"The belief of some governments that nuclear weapons are a legitimate and essential source of security is not only misguided, but also dangerous, for it incites proliferation and undermines disarmament. All nations should reject these weapons completely — before they are ever used again. This is a time of great global tension, when fiery rhetoric could all too easily lead us, inexorably, to unspeakable horror. The specter of nuclear conflict looms large once more. If ever there were a moment for nations to declare their unequivocal opposition to nuclear weapons, that moment is now."

"We applaud those nations that have already signed and ratified the Treaty on the Prohibition of Nuclear Weapons, and we urge all others to follow their lead. It offers a pathway forward at a time of alarming crisis. Disarmament is not a pipe dream, but an urgent humanitarian necessity."

"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?"

"Today, every inhabitant of this planet must contemplate the day when this planet may no longer be habitable. Every man, woman and child lives under a nuclear sword of Damocles, hanging by the slenderest of threads, capable of being cut at any moment by accident, or miscalculation, or by madness. The weapons of war must be abolished before they abolish us."

"I still agree with [what I wrote]. Ultimately, the world will be safe only when all the nuclear states follow South Africa’s example and dismantle their nuclear weapons."

"One of the possible causes of human extinction will most likely involve the functioning of the ozone layer [...] Many people appear to forget that we are a part of nature and that we are animals, not machines. We require habitat, and because we are large animals, our biological requirements are quite different than small mammals such as mice. Large animals tend to live longer and are therefore subject to far more issues such as disease. Disease often begins with exposure to certain chemicals, toxins, or other animals which harbor viruses or other microbial infections. The current coronavirus pandemic makes it clear just how precarious our existence really is. Nobody is guaranteed tomorrow."

"The future of mankind is going to be decided within the next two generations, and there are two absolute requisites: We must aim at a stable-state society [with limited population growth] and the destruction of nuclear stockpiles. … Otherwise I don't see how we can survive much later than 2050."

"Humans got here in an ecological context surrounded by uncountable and unknowable interdependencies. It’s enormously risky to let our ecological ignorance suggest that we don’t need what we don’t understand—especially when we have ZERO evidence that humans can survive in a world depleted of its biodiversity. I get angry thinking about people who blithely make such a counterfactual and irreversibly devastating assumption. Nor should we imagine ourselves as being able to survive the sixth mass extinction we have initiated. Animals higher on the food chain have a harder time in such epochs. Humans are voracious (big brains to feed and a lot of un-furry surface area to keep warm), and therefore are ecologically expensive. If the Earth tightens its belt, don’t assume that humans will fare well. We are summer children borne of “good” times, where “good” translates to “biodiverse.” Cleverness is no guarantee against starvation, as countless clever humans who have starved can’t tell [us]."

"I grew up in the 1980s in the UK, and we had the Campaign for Nuclear Disarmament, all that. People were very, very aware. When I was 13, me and my friends, we were convinced we would die in a nuclear holocaust… What I remember from the '80s is that the fear of nuclear war had receded in favor of fear of environmental destruction. It was almost like we couldn't sustain the fear of it for that long. We have a complicated relationship with our fear. And yes, Putin has been using that doomsday threat and that fear to saber-rattle. It's extremely unnerving."

"The flame from the angel's sword in the Garden of Eden has been catalyzed into the atom bomb; God's thunderbolt became blunted, so Man's dunderbolt [sic] has become the Steel Star of Destruction."

"Imagine a room awash in gasoline, and there are two implacable enemies in that room. One of them has nine thousand matches. The other has seven thousand matches. Each of them is concerned about who's ahead, who's stronger. Well that's the kind of situation we are actually in. The amount of weapons that are available to the United States and the Soviet Union are so bloated, so grossly in excess of what's needed to dissuade the other, that if it weren't so tragic, it would be laughable. What is necessary is to reduce the matches and to clean up the gasoline."

"Every thinking person fears nuclear war and every technological nation plans for it. Everyone knows it's madness, and every country has an excuse."

"Consider again that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar", every "supreme leader", every saint and sinner in the history of our species lived there — on a mote of dust suspended in a sunbeam."

"To recognize one’s own insanity, is of course, the arising of sanity, the beginning of healing and transcendence."

"Despite nuclear abolition being the long-awaited wish of all A-Bomb survivors, there are still more than 13,000 nuclear weapons in the world, with nuclear states continuing to modernize their nuclear forces. Moreover, nuclear disarmament continues to stagnate, further exacerbating global tensions."