Hong Kong protesters have already won the battle – to avoid a full-blown war, they must scale back now

When coups happen, the rebels usually try to secure the airport. So the Hong Kong pro-democracy protesters who seized control of Hong Kong international airport had certainly made their point to the authorities – that mass protest is capable of paralysing this major hub, and that they can go further in their passionate defence of their limited freedoms. When the protesters managed to rumble a couple of undercover Hong Kong police officers and detain them temporarily, the danger of massive intervention by the authorities was at its height. Fortunately, the riot police exercised restraint, and they and the paramedics managed to retrieve their colleagues.

However, following this incident, the earlier invasion of the Legislative Council building, and the widespread disruption over recent weeks, the protesters should be careful that they do not succeed too well, and push Beijing into a corner it cannot escape from. This is in the sense that Beijing perceives that what is going on is in fact an attempt at a localised coup, and secession from the People’s Republic, which is something that it can never permit.

So it was predictable as well as ominous that lorry-loads of Chinese troops later arrived in the vicinity of the airport. No one can be sure of their intentions. It may be that it is a persuasive show of strength, designed to cool the ardour of the protesters and encourage them to go home, or at least carry on with their activities on the streets. Alternatively, it could be the precursor to a bloody suppression of what the Chinese are calling – tellingly – “terrorism”.

As we have seen all too often in the history of communist China, the leadership fears losing control and another fracturing of the nation that Mao did so much to reverse in the Long March that ended in 1949. Hong Kong, like Taiwan, Tibet and the western Muslim province of Xinjiang will not be allowed to go its own way. There should be no mistaking president Xi Jinping’s determination about that. He has already made himself president for life, and has imprisoned millions of Uighur Muslims in “re-education” camps in Xinjiang. China has even intervened in the Kashmir crisis (where China occupies a slice of the disputed territory). Mr Xi is not a man to underestimate.

This is a new, richer, more economically powerful China that has emerged since Deng Xiaoping initiated a radical programme of reform three decades ago. It is a China that is more assertive abroad and at home, and even less tolerant of western powers trying to push it around. Witness, then, the US-China trade wars, and the dismissal of UK protests about the course of events in Hong Kong.

Something thus needs to be done to de-escalate the growing and dangerous tensions. The protesters have a perfect right to make their views clear. They are also within their rights to appeal to Britain and the United Nations to protect the rights that were guaranteed by international treaty when Hong Kong returned to full Chinese sovereignty in 1997. They are also right to be worried about the slide towards more control by Beijing.

Yet the Chinese-nominated governor of Hong Kong, Carrie Lam, has already effectively killed off the judicial reforms proposed some weeks ago. This came not least because of the size of the civil disturbance, and is unlikely to re-emerge as a draft bill again. The Hong Kong protesters have, in other words, already won the battle about the new law on extradition to the mainland. They should recognise that, and hold their protests in reserve until and unless the central authorities assault their liberties again.

If they do not, then the protesters face the real possibility of mass violence, ordered by an elderly leadership haunted by the weak, divided China of the past, with an absolute ideological belief in the role of the Communist Party in guiding and guaranteeing China’s progress.

They should not give way simply because Beijing is bigger than they are, and has soldiers and tanks to make its case. They should, though, scale back the protests, because they have, for all intents and purposes, already won the day.