The biggest beneficiary of Vladimir Putin’s depredations, at least in the short term, may be China.

It’s not just that, with his European markets constricting, Putin is easy pickings for Chinese negotiators when he comes selling natural gas.

It’s also that he makes China look good by comparison — which is not easy, given that China is in the midst of a historic crackdown on civil society and freedom.

With Russia invading and occupying a neighboring nation, and repeatedly lying about it, China’s bullying in the South China Sea seems tame.

And with opposition politicians being gunned down gangland-style within walking distance of the Kremlin, China’s harassment and imprisonment of human rights activists comes across as almost civilized.

Yet for all of Putin’s barbarities, China may pose a greater challenge to the democratic world — and to the next U.S. president — because its turn toward repression has upended the basic assumptions of U.S. policy toward China since it opened to the world decades ago.

The crackdown itself is no longer in dispute. Last year President Xi Jinping and the Communist Party “unleashed the harshest campaign of politically motivated investigations, detentions, and sentencing in the past decade, marking a sharp turn toward intolerance of criticism,” Human Rights Watch said recently in its annual world report.

From the beginning of Deng Xiaoping’s reforms, party control coincided with “an expansion of space for citizens and society,” as the organization’s senior Asia researcher Nicholas Bequelin told me during a recent visit to Washington.

That loosening ended in 2007, as the Beijing Olympics approached, and China began going in the opposite direction. The trend has accelerated since Xi took over two years ago. “The space is not expanding any more, and the walls are getting higher,” Bequelin said.

Party officials are reasserting ideological control in universities. They have reined in media that dared criticize the regime. Tens of thousands of security agents — China’s internal security budget not long ago surpassed the also-expanding military budget — prowl through digital space enforcing loyalty to the regime.

As Maya Wang, another Hong Kong-based researcher for Human Rights Watch, said, authorities are arresting the most respected lawyers and civil activists, people whose activities were previously encouraged or at least tolerated, and who were thought to be invulnerable to arrest. The message, she said, is that “no one is safe.”

Gao Yu, 70, an eminent journalist who has won numerous international awards, was picked up last spring. So was Pu Zhiqiang, 50, a respected lawyer who had defended artist Ai Weiwei and other prominent clients. A Nobel Peace Prize is no shield: Liu Xiaobo remains in prison for his peaceful advocacy of democracy. Age is no shield, either: Huang Zerong, 81, who crossed authorities by publishing memoirs of victims of past Communist purges, recently spent five months in detention on a charge of “causing trouble.”

“As the circle of arrests expands, no one is left to complain, and international concern is numbed,” Wang said.

In the long run, this is a problem for China first and foremost. The increasing freedom of its citizens underpinned its remarkable economic growth, and if their creativity and entre­pre­neur­ship are stifled, if they are unable to communicate freely with each other and the outside world, it’s unlikely China can keep growing as fast. Meanwhile, with the most civilized forces crushed — the advocates of gradual, peaceful liberalization — then as the economy slows the ugliest voices of nationalism and intolerance will rise.

All of this disturbs Washington’s comfortable assumption that Western engagement — trade, investment, student exchanges — would inevitably promote China’s gradual movement toward democracy and acceptance of international norms. That was the rationale for normalizing trade under President Bill Clinton, and two subsequent administrations have accepted the premise.

They’ve also assumed that issues of human rights and the rule of law could be steered onto a side track while the economic and political relationship chugged unimpeded on its own more important track.

Now it’s obvious that the two can’t be so easily separated. U.S. technology firms are kept out of China, with political control and protectionism mingled as inseparable motives. Chinese reporters are welcome in the United States, but China picks and chooses who can report from Beijing — and which news sites Chinese people can read. That has business implications, too. State-owned enterprises under party control have more, not less, sway than they did 10 years ago; does it make sense to pretend that they will follow the normal rules of capitalism? On issues ranging from cybersecurity to counterterrorism and beyond, the nature of China’s regime makes cooperation dicey.

Engagement cannot be abandoned; the two nations are way past that, given the economic ties they have forged. But for the next president, finding the right way to engage with a rising power that is writing its own rules may make saving Ukraine seem easy.

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