If China has indeed shot down one of its old satellites, it has opened a conversation that the US never wanted to have. It would be wrong to call this the opening of a new front of confrontation in space. Such a strike, if confirmed, would be merely an inevitable step in the rise of both countries’ technological sophistication and occupation of orbital space around the Earth.

For those whose imaginations run easily to thoughts of extraplanetary warfare, it is worth remembering that endeavours in space are small in every dimension, except cost, compared with those on Earth.

Any tension between China and the US in that domain will be dwarfed by that down here: economic, political and military.

All the same, such a strike would put pressure on the US to do what it has so far refused: begin talks with other countries about limiting a so-called arms race in space. The US has declined to acknowledge that such a possibility exists, while, in a series of proprietorial-sounding statements, has challenged the right of any other country to move freely about space.

It is no bad thing if the US now has reason to retreat from that isolated position, where it has absolutely no support from other countries within the United Nations, and to at least discuss the regulation of the increasingly crowded neighbourhood of space.

Russia did a magnificent job yesterday of disparaging reports that a Chinese ballistic missile had destroyed a satellite. Sergei Ivanov, the Defence Minister, drew on his deep vocabulary of scorn to pronounce them “abstract” and “highly exaggerated”. Perhaps.

But if they are confirmed, they do raise questions about many countries’ vulnerability to attack

on this new front.

The prospect that alarms the

US, in particular, is that so much

of modern commerce, government and defence relies on communications satellites in orbit. The prospect that they are vulnerable to missiles from other countries is not comfortable.

China and Russia may have such capability; Iran has its own satellite and plans for a launch vehicle; while about 40 countries have some presence in space.

The US has not looked warmly on proposals within the UN to begin talks about banning an arms race in space. On the last vote, it was alone against 160 other countries in voting not to start such talks. It has one strong argument: that such talks may be diverted easily by other countries, including those with no presence in space, to curtail all kinds of US activities there. The US, so far ahead of all other countries in space, already feels itself to be the target of broad-brush anti-Americanism within the UN, and is not keen to expose itself to a new assault.

It has brought some of the criticism on itself. The new National Space Policy, which President Bush signed in October, is provocative on two fronts. It swings the emphasis of US space activities from science and exploration to security and defence. And, in a declaration that attracted much international comment, it asserts the right to deny access to space to anyone “hostile to US interests”. It is one thing to assert a right, but another to justify it; so far the US has not done that, other than by its pre-eminence. It appears that China may have fired an opening shot in a debate that it is now determined the US should recognise.

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