The Chinese are in the wrong in seizing an American hydrographic survey drone. It is worth noting that whether it was genuinely engaged in scientific research or whether it was engaged in some sort of defence surveillance activity is irrelevant. It was operating entirely lawfully on the high seas and the Chinese had no right to seize it.

John Pilger’s tremendous new documentary The Coming War With China explains Chinese motivations. China is ringed by 200 US military bases and installations, far from any State of the USA, in an unabashed display of American Imperial power. China by contrast has very few military outposts outside China at all and shows remarkably little interest in territorial ambition, given China’s current economic power. The stories of US exploitation and duplicity recounted in the Pilger documentary are overwhelming, and of course the entire venture is a massive transfer of money from struggling US taxpayers to the arms industry. One is left with a feeling of surprise that the Chinese reaction to naked US threat is so calm and not paranoid.

But while this may make Chinese behaviour understandable, it is none the less wrong in law. The UN Convention on the Law of the Sea makes absolutely clear that artificial islands cannot make a maritime claim – articles 60 and 80 refer. This law is both right and necessary. If we accept that artificial islands can generate a maritime claim, then the great powers will be racing all over the globe to build them and claim the oceans, to the detriment of the rest of the world, and especially developing countries.

US behaviour is aggressive on a global scale. The Chinese reaction represents blowback. But that does not make it either right or legal.