In a weird new Cool War twist, Washington is demanding that China bring home agents it sent secretly to the US to pressure corrupt Chinese officials and businessmen to return home and be punished. The shoe’s on the other foot for the US, which has in the past frequently sent its own operatives to other countries without permission to grab not just terrorists but criminals, too.

But the turnabout isn’t what’s most striking about this episode. Rather, the most important thing about China’s secret efforts is why China thinks they’re necessary at all. After all, the US is generally happy to repatriate criminals to their countries of origin.

True, there’s no bilateral extradition treaty between the US and China. But formal extradition isn’t the only way to send criminals home. When a person is on US soil illegally, the government can simply remove the person. And it’s very probable that someone who fled corruption charges in China has violated some aspect of US immigration law.

So why isn’t China teaming up with US law enforcement to bring its criminals home? For that matter, why doesn’t China just seek an extradition treaty? The reasons it thinks it can’t are complicated and interesting — and reveal some highly significant aspects of President Xi Jinping’s signature anti-corruption campaign.

Start with the most immediate security risk that China believes it might face if it cooperated with the US to bring home big-ticket corrupt Chinese: old-school, Cool-War-style defection. We know that Chinese officials afraid of prosecution are prepared to take this step. In 2012, Wang Lijun, the powerful police chief of the major city of Chongqing, tried to defect by walking into the US consulate in the neighbouring city of Chengdu. In the end, the US gave Wang back to the Chinese authorities — but not before the police chief had begun the chain of events that lead to the fall of Bo Xilai, Chongqing’s mayor and a high-ranking, well-connected Communist Party official.

If the US knew exactly who was on China’s most-wanted list, it conceivably could approach those businessmen or officials, let them into the country, and try to trade asylum for information — an outcome that the Chinese government wouldn’t like. In practice, the risk of such an event might be low. But the cost could potentially be high. China’s ongoing distrust of the US is therefore one reason that it hasn’t chosen to collaborate with the US government on repatriating suspects.

Probably more worrying from the Chinese side than defection is political embarrassment. China’s corruption problem is extraordinarily serious. Xi Jinping knows very well that the future of the Chinese Communist Party as a ruling class depends on defeating corruption, or at least cutting it back to the level where it doesn’t threaten the moral authority of party rule.

For a party seeking to maintain its legitimacy, fighting corruption therefore always requires a delicate balance. On one hand, the party must be seen to be confronting corruption at the highest levels and punishing those responsible. On the other hand, it must be careful not to create the impression that all senior officials and successful businesspeople are corrupt.

Within China, Xi can strive to maintain this fine balance — because through the party he controls the media and the legal system. Outside, however, it’s much harder, which is why China excluded Bloomberg News and New York Times reporters from the country after their organisations published expose of public corruption.

Going to US officials, cap in hand, and asking for help in returning corrupt Chinese figures would deepen Chinese embarrassment about the extent and depth of its corruption. It would be a loss of face for the government and indeed the whole nation. And it would be very unlikely to remain secret, given the norms of news publication in the US as opposed to China.

It would seem less embarrassing for China to negotiate a bilateral extradition treaty with the US. Indeed, China has trumpeted its 39 extradition treaties as part of publicising its anti-corruption campaign. Routinising police cooperation would take some of the sting out of seeking help. And since China would be offering to help the US with its fugitives, too, the whole process would seem to put the countries on an equal footing.

Yet China may be worried about the risk of being publicly rebuffed by the US from signing a treaty, on the ground that its justice system isn’t sufficiently fair to warrant a mutual agreement. The US has extradition treaties with roughly 100 countries. They’re not all perfect democracies, and they don’t all have excellent justice systems. But they’re all, or almost all, basically decent countries that will provide something like a fair trial to the accused. (In some cases, the treaty was signed under those conditions which subsequently changed.)

China’s justice system isn’t in that league yet — at least not where anti-corruption prosecution is concerned. No one really doubts that those officials convicted of corruption have broken the law. But there’s no system of open trials or judicial decision-making independent of party pressure. China’s judiciary is understood by all to be subordinated to the needs of the nation, as interpreted by the Communist Party and Xi Jinping. The anti-corruption initiative is inevitably and necessarily political — and almost guaranteed to remain so.

In the new Cool War, there are sometimes ways around political difficulties or embarrassment. Perhaps China and the US could someday reach an informal, case-by-case mechanism for deporting suspected Chinese wrongdoers from the US. But in the meantime, China’s own judicial system — and the political imperative of Party survival — stands in the way of official cooperation. Expect the undercover agents to keep coming.

—Washington Post