The people are on your side. Why arrest them?

So why arrest him? Why worry about him at all? In even a modest scheme of things, Ai is unimportant, lacking access to a mob, a party, weapons, Chinese TV and most of the other modes of making big trouble fast. But to a rising nation, confident, muscular and fulfilling its peoples’ dreams of prosperity, what threat could he possibly represent? It’s like David Cameron demanding the arrest of Grayson Perry.

This isn’t the first time that Ai has had problems with the Chinese State. He was beaten up by police in Chengdu in 2009 when trying to testify at the trial of someone who had been investigating shoddy construction before a disastrous earthquake, and he has been subject to constant bureaucratic harassment and cyber-hacking.

And he isn’t alone. According to Human Rights Watch and Amnesty International, probably the biggest crackdown on dissent for a decade has been going on since the beginning of the year, largely unremarked upon in the West. As many as 25 human rights lawyers and internet activists have been arrested or somehow magicked out of the public eye by the authorities, and as many as 200 more have been subject to lower level intimidation.

There have been allegations of torture and ill treatment. Meanwhile, internet restrictions have been tightened, as have curbs on foreign reporting from China. Those charges that have been brought include “incitement to subvert state power and overthrow the socialist system”, the scope of which can be judged from the ten-year prison sentence handed out just two weeks ago to one democracy activist, Liu Xianbin, for the crime of publishing articles on foreign websites.

Enough lists. The number of those imprisoned is, in one sense, very small. They are the merest drops in the Han ocean, compelled by some strange obstinacy to displease the almost omnipotent high-ups in the One True Party. Their motivation is another story; what we are concerned with here is why the tiger runs so scared.

It is often reported back by those who have managed to enjoy some frank discussions with major Chinese figures that what they fear most is corruption, and public reaction to it. Last year, there was the famous “my father is Li Gang” case, in which a young drink-driver who killed two people declared himself beyond the reach of the law because his father was a high local official. The story became viral and quickly represented the indignities that Chinese people suffer at the hands of unelected and unaccountable officials.

Of course, the party is against such corruption. Periodically, it steps up its own anti-corruption campaigns, temporarily licenses whistleblowing and investigative journalism, executes some culprits and hopes that it has done enough. But its problem is that such campaigning very easily becomes threatening to the party itself.

Take the case of Zhao Lianhai, the journalist whose infant son was one of the children made ill in the appalling melamine scandal of 2008. Melamine is a chemical that was added to watered-down milk to raise its protein count. Six babies died and 50,000 were hospitalised with kidney damage, one of whom was the child of Mr Zhao. He started up a website to comment on the tragedy and encourage other parents to take legal action.

Last autumn he was arrested in Beijing, tried in a suburban court, found guilty of “inciting social disorder” and sentenced to two and half years in prison. And then, in February, Mr Zhao disappeared. His Chinese lawyers were told that he no longer required their services and that he had been released — but no one knew where to. He had, as they say, “disappeared like steam”, almost certainly into house arrest, neutralised both as a campaigner and a symbol.

Again (in terms of their own reasoning), one asks why? You hear various arguments from Chinese sources and apologists. One of the more sophisticated is that the creation of interest groups insisting on negotiation of their views would distract government from the business of economic management and damage business confidence in China.

Last month, I was in Hong Kong, debating democracy with Professor Pan Wei, director of the Centre for Chinese and Global Affairs at Peking University. His argument was this: it is no more practical to allow the people to run a country than to allow the passengers to fly a plane. Democracy for him was cacophony and chaos. Better to keep the thing in the hands of an enlightened bureaucracy. Chinese people, he said, agreed with him.

All right. If that’s true, why would you have to bang up Mr Zhao, nick Ai Weiwei, stop Liu Xiaobo from collecting his Nobel prize and disappear a clutch of human rights lawyers? If the people are on your side, then why worry?

Despots, like everyone else, imagine themselves to be virtuous. Especially so when they appear with modest smiles and office ties rather than epaulettes and balcony-bombast. Somehow they know what the people (whom they love) do not, which is how the show can be kept on the road. And that is why they are, in the end, fated to resist any attempt to question them and to hold them to account.

Of course, we will be told, one must understand the particularity of China: its fearsome history, its fear of chaos, its collective (as opposed to individual) ethos, its Confucian tradition — all making it resistant to democracy and, collaterally, to human rights.

Maybe. But what do we notice about authoritarians, from Benito to Saif, via Hosni and Honecker? That there are always a million reasons not to give up power, that it’s always my way or the Ai Weiwei away way.