What are the positions on nuclear weapons?

Nuclear weapons act as a deterrent for war

Question: What are the positions on nuclear weapons?
Position‹2 of 3›: Nuclear weapons are essential in the modern world
Argument: Nuclear weapons act as a deterrent for war

The threat of nuclear weapons keeps powerful countries from engaging in conflict. The introduction of these weapons into the world has allowed for leaders to be more cautious with their foreign diplomacy for fear of the destructive consequences of nuclear weapons.

The argument

Nuclear weapons serve as a deterrent for war. The most powerful countries in the world currently remain carefully peaceful towards one another because of the threat of nuclear war, and the word carefully is doing real work in that description: the peace is not the product of goodwill or of resolved disputes, but of calculation. Rivalries persist between these states, and they are pursued through means short of direct confrontation because direct confrontation carries a cost none of them is willing to risk. Deterrence theory explains why that cost cannot be discounted, through the principle of mutual assured destruction. MAD refers to the idea that if one country uses nuclear weapons against another country that also has them, the destruction would effectively annihilate both. What makes this stabilising is that it removes the possibility of winning. An aggressor contemplating a conventional war can hope to come out ahead, and that hope is what makes the war worth starting; under MAD no such outcome is available to either side, so the calculation that ordinarily leads to war between great powers never completes. The historical claim offered in support is that this is what the record shows. The concept of MAD allowed for the end of the cold war, and has since been the reason no large-scale conflicts have erupted in the modern world — a period in which rival powers had ample cause to fight and did not. The conclusion runs the other way as well. If there were no longer nuclear weapons, and the threat of nuclear war no longer loomed above world leaders, countries would have fewer reservations about global conflict, because the one consideration that reliably stops them would have been removed.

Premises

[P1]The threat of nuclear war keeps the world's most powerful countries carefully peaceful, as mutually assured destruction means using nuclear weapons would annihilate both sides. [P2] Without that deterrent, countries would have fewer reservations about global conflict—MAD helped end the Cold War and has prevented large-scale conflicts since. [C] Therefore, because nuclear weapons act as a deterrent for war, they are essential in the modern world.

Counter-arguments

Many people argue that recent studies have disproven the deterrence theory. According to Benoît Pelopidas, the scientific director of the masters programme in international security at Sciences Po (Paris), "threats intended to deter may have adverse effects, as can any other public policy. If one needs to constantly establish the credibility of a deterrent threat based on nuclear weapons, this will obviously lead to more risk-taking". The threat of nuclear weapons will not always act as a deterrent, and can actually cause the start of a conflict.

Rejecting the premises

[Rejecting P1] The absence of war between nuclear powers is consistent with deterrence but does not establish it: the same decades contain alliance structures, trade dependence and the memory of two world wars, and the counterfactual the premise relies on cannot be observed. [Rejecting P2] Attributing the end of the Cold War to mutually assured destruction passes over the political events that ended it, and "no large-scale conflicts" sets aside the proxy and regional wars fought throughout the period — while, as the counter notes, maintaining a credible threat can itself invite risk-taking.