But scholars such as Larry Diamond and Minxin Pei have noted that dictatorships tend to have a roughly 70-year lifespan. At some point, the revolutionary fervor that sustains the first generation of leaders and the will to power that sustains the second gives way to the policy failures, mounting discontents, outside shocks and inner doubts that prove the undoing of the third.

Especially when the regime experiences some kind of blunt trauma, either in the form of a foreign-policy fiasco, an economic shock, or a moral outrage. In its attempts to respond to Hong Kong’s protests, Beijing risks all three.

A policy of hoping the protesters discredit themselves or simply run out of steam shows no sign of working. A Tiananmen-style crackdown would underscore the regime’s brutishness and incompetence, destroy Hong Kong as a global financial capital, and spur China’s neighbors to arm to the teeth and draw closer to Washington. Accommodating the protesters’ demands, above all the granting of genuine universal suffrage, is the right thing to do, but introduces a democratic principle fatal to the regime’s self-preservation.

Hence the looming crisis. It could be defused, if Beijing guarantees amnesty for all nonviolent protesters and removes the troops it has brought in from the mainland in exchange for a meaningful process of negotiation. Or it could be “solved” through some form of hyper-aggressive policing that stops short of an outright massacre. But that only puts a lid on discontents that will continue to boil.

Skeptics will note that China’s profound cultural aversion to the prospect of political disunity and chaos may incline the mainland Chinese to approve a hard government line with Hong Kong. And nothing in Xi’s actions or manner suggests he suffers from Gorbachev-like misgivings about the nature of the regime he rules or of his right to exercise power by whatever means necessary.

But if the regime’s travails prove anything, it’s that China’s current despot is no more enlightened than despots elsewhere, and China’s people are no less eager to have what people have elsewhere: justice, fairness, rights, freedom from fear, freedom itself. In China’s looming crisis, the human condition shines through.

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