Pop Quiz: Which Asian despot (hint: he was responsible for the deaths of tens of millions of his country-men and had launched a surprise attack against U.S. military forces on the Korean Peninsula) said these crazy things about nuclear war, clearly making his country unfit for their possession: “We have a very large territory and a big population. Atomic bombs could not kill all of us…. We would still have many people left.”

If you guessed North Korea‘s Kim Jong Un, who has regularly uttered similarly hair-raising threats of nuclear war while rattling his miniscule nuclear sword, you would be wrong. The correct answer is China’s Communist leader Mao Tse-tung, who is said to have shared the above quote with a visitor to Peking in 1957.

The Chairman was so insouciant about nuclear weapons, dismissing them as teeth in the papier-mâché tiger, that as China took steps to join the nuclear cartel, the United States and the Soviet Union approached each other at various times in the 1960s about cooperating in a preemptive strike to strangle Red China’s nuclear baby in the cradle.

Thankfully, neither did. In fact, history demonstrates their restraint was the correct response to China’s nuclear development, Mao’s looney rhetoric and bloody rule notwithstanding. Indeed, the China case teaches two important lessons for how the United States and the rest of the international community should to respond to North Korea’s nuclear ambitions today.

First, when considering the consequences of another state gaining nuclear weapons, we should not make too much of its leader’s bombast. Talk is cheap and this is equally true for barroom braggarts and tin-pot dictators. What counts is behavior, particularly what the leader does in terms of foreign policy. Even murderous dictatorships like Mao’s have behaved surprisingly cautiously once they acquired nuclear weapons. Their caution had little to do with wisdom or altruism and everything to do with self-interest: Dictators are all about surviving and remaining in power.

Second, given that dictators, particularly atheistic communist despots, sole goal in life is to maintain their tenuous grip on power in the here-and-now, they are in fact relatively easy to deter, at least in terms of nuclear use. Provoking a nuclear war with another country is the surest way for a despot to lose power and life.

In addition, China in the 1960s was wracked by domestic instability as the Great Cultural Revolution nearly tore the country apart. Mao’s Red Guards killed millions and drove the country to the brink of civil war. But throughout it, the otherwise immoderate regime’s nuclear behavior remained moderate. China developed only a modest arsenal and its leaders apparently regarded it solely as a means to deter attack from abroad.

This history lesson is applicable to North Korea today. Let’s assume the worst case (on which there is not consensus in the U.S. Intelligence Community at present), that North Korea now has, or is close to achieving, the ability to attack the continental United States with a handful of nuclear weapons. How does that change things and what should we do in response?

Like Mao, Kim is a ruthless and blood-thirsty tyrant whose sole objective in life is to maintain his grip on to power. His nuclear arsenal is a trump card preventing outside countries from using military force to undertake regime change the way the United States did with Saddam Hussein in 2003. Beyond that, Kim will discover that his pygmy arsenal will buy him little more than deterring external military intervention.

Moreover, deterrence works both ways: If North Korea’s arsenal will dissuade the United States from invading the Hermit Kingdom (an unattractive undertaking even without the nuclear factor in the equation given the high costs of even conventional war on the peninsula and the diplomatic complications that it would ensue with China), the U.S.’s arsenal will deter North Korea from actually using its rudimentary nuclear capability in all but regime-threatening contingencies.

President Donald Trump is hardly exaggerating when he says that the U.S. could inflict historically unprecedented damage on North Korea. America has nearly nuclear 5,000 warheads compared to North Korea’s 30 to 60. All of ours are reliable and deliverable; the same cannot be said for Kim’s small arsenal.

Given this disparity, the United States can credibly threaten not only Kim’s hold on power but his very existence. While the president was undoubtedly not thinking along these lines, the “fire and fury” he threatened is actually a very robust deterrent which means that as with Mao, a nuclear Kim is not the end of the world.

Commentary by Michael Desch, a professor of political science at Notre Dame and director of the Notre Dame International Security Center. He is co-author of the book “Privileged and Confidential: The Secret History of the President’s Foreign Intelligence Advisory Board” with K. Michael Absher and Roman Popadiuk. Follow him on Twitter @mcdesch.

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