Other countries model this behavior – escalates every other conflict and causes extinction.

The problem with succumbing to Putin’s demands is that doing so is not necessarily the best way to minimize the dangers of nuclear war. Because a rational leader would not undertake a policy whose costs outweighed the benefits, sometimes leaders bluff, feigning that they are willing to face costs far greater than warranted in order to intimidate their adversaries into surrender. Surrender here, however, can increase the prospects of nuclear war going forward.

One of the foremost advocates of this nuclear bluffing strategy was Richard Nixon. As he explained his approach to his White House chief of staff H. R. Haldeman, I call it the Madman Theory, Bob. I want the North Vietnamese to believe I’ve reached the point where I might do anything to stop the war. We’ll just slip the word to them that, ‘for God’s sake, you know Nixon is obsessed about Communism. We can’t restrain him when he’s angry — and he has his hand on the nuclear button’ and Ho Chi Minh himself will be in Paris in two days begging for peace.

Nixon and his national security adviser Henry Kissinger tried to carry out this strategy in October 1969, hoping to frighten the Soviet Union into pressing North Vietnam to accept American terms. On October 6, Kissinger ordered the secretary of defense to conduct a “series of increased alert measures designed to convey to the Soviets an increasing readiness by U.S. strategic forces.” The next week, the Strategic Air Command put on alert 176 bombers and 189 refueling tankers. Nixon met with the Soviet ambassador, displaying, according to an impressed Kissinger, the “guts of a riverboat gambler.” On October 26, the Strategic Air Command flew six armed B-52 bombers over Alaska. But, despite the intimidation, Moscow did not compel Hanoi to surrender – and (fortunately) nor did Soviet leaders panic and launch a preemptive strike on the United States.

The political science literature shows that the madman strategy generally doesn’t work. The biggest problem with the strategy is, in the words of Stephen Walt, an advocate of realism in international relations:

When other states deal with a powerful but unpredictable leader, they may tread carefully but they aren’t going to make big concessions. After all, if a madman is dangerous now, doing anything that makes them more powerful just makes them more dangerous later. Appeasement is sometimes a smart diplomatic strategy, but only if one believes that making concessions will remove grievances, reduce suspicions, make the other side more benign, and allow mutually beneficial relations to emerge.

Imagine what would happen if Washington responded to Putin’s nuclear bluster by stopping its weapons supplies to Ukraine or lifting its sanctions.

The Kremlin, now with a proven method of getting its way, could then demand surrender from Georgia and Moldova, two former Soviet republics where Russian troops currently hold contested territory. And when the United States and NATO refused to provide arms to these governments (because, after all, one doesn’t want to risk nuclear war), the two countries would have little option but to submit. But why stop there? If Russia then demanded (with appropriate rhetoric and missile tests) that NATO troops be removed from the Baltic states, would it be worth risking madman Putin escalating to nuclear war? So best comply. And if it then further demanded that no NATO arms be provided to these former components of the Soviet Union, again, why provoke the Bear? But at some point, either Moscow or Washington will miscalculate — will NATO back down? is Russia bluffing? — and we’ll be in the midst of a nuclear war.

And Putin wouldn’t be the only one to try to take advantage of this strategy. Would his success encourage other nuclear bullies? Might Israel then make demands of Iran, to which Tehran would have to give in lest it face Armageddon? Might China demand that the United States stop arming and even trading with Taiwan, facilitating a bloodless conquest? Might North Korea demand that South Korea and Japan subsidize its economy?

But giving in to Putin’s threats wouldn’t only encourage continuing acts of nuclear extortion. It would also provoke the potential victims of this extortion to rush to acquire nuclear arms of their own as a means of self-protection. South Korea, Taiwan, Japan, Iran, Saudi Arabia, UAE, Qatar, Egypt, and others would inevitably seek to become nuclear weapons states (if they are not already doing so). Some experts have claimed that widespread nuclear proliferation would be great, because no one would ever go to war again, fearing nuclear retaliation. But as most analysts understand, the risks of accidental, inadvertent, or escalatory war, or terrorism, or sabotage increases exponentially with the number of nuclear weapons states.

To be sure, the historical record suggests that nuclear arms have not been very successful as a coercive tool. (Consider that possession of nuclear weapons didn’t allow the United States to prevail in Vietnam or the Soviet Union in Afghanistan.) But if nuclear threats gave the Russians a victory in Ukraine (for that’s what a cut-off of Western military supplies would mean), the calculus would change dramatically. Nuclear weapons expert Todd Sechser has observed:

Russia has given us a vivid reminder that nuclear weapons are not a magic wand. As the war began, Vladimir Putin made several nuclear threats – both explicit and implied. But the fear of nuclear escalation has not intimidated Ukraine into submission. Nor have these threats dissuaded the West from imposing crippling sanctions on Russia and providing military aid to Ukraine. If anything, Putin’s nuclear bellicosity has only fueled the international backlash against Russia. The war has thrown a spotlight on the political limits of nuclear weapons, and dictators with nuclear ambitions should take note.

If instead, NATO had given in or gives in to Putin’s demands, the lessons for leaders with nuclear ambitions would be rather different.

Appeasement, then, has its dangers, setting off dynamics that might increase rather than decrease the risks of nuclear war. But military build-up and the logic of deterrence have their dangers as well, as we know from many historical examples. International relations scholars and peace researchers has long identified the “security dilemma” as a major cause of war: when one country takes steps to increase its own security that in turn decrease the security of its adversaries, the resulting countermoves end up reducing everyone’s security. (The eastward expansion of NATO was a classic example of this dynamic.) So while it would make good sense to call for the scaling back of aid to Ukraine if there were a real danger of nuclear war, giving in to Russian demands if they were a bluff might actually increase the dangers of nuclear war.