China's achievement in landing a spacecraft Chang'e 4 on the far side of the moon, announced by Beijing, has ramifications that go far beyond the simple statement of this being a "first" for mankind.
It puts China on the map of international space exploration on a par with the existing space powers of the United States and Russia - the European Union to a lesser extent - but also adds a new dimension. It is the first time a landing has been attempted on the far side of the moon, with the particular communications challenges this entails, and it has been a success.
The first response from the US space agency, Nasa, was generous, as scientists to scientists: what China had managed was a "first for humanity and an impressive accomplishment". The response in political and military quarters in Washington, as in Moscow, however, is likely to reflect trepidation. There is now a serious newcomer to be considered.
China was late into space, sending its first astronaut into orbit in 2003 - 40 years after the Soviet Union and the US were embarking on their space race. Now Beijing has done something neither of the other two space powers has done - that may well be because they had other priorities for their space programs, such as manned flight, human survival in space and the fascination with distant planets, first of all Mars.
After Neil Armstrong became the first human to walk on the moon - a US triumph that provided some consolation for the shock that a Russian, Yuri Gagarin, became the first man to go into space - there was a sense that the moon had been "done". Greater challenges awaited. Will that change now, and could the moon become a potentially contested territory?
At a popular level, space has not lost its power to fascinate. The proximity of the moon and the mystery of its far side guarantee that China's latest mission will command global attention beyond the scientific space fraternity. It will enhance China's international standing, and could well inspire an interest in China and space among young people, as the US-Russia space race once did.
The mix of admiration and anxiety that accompanied early Soviet space successes helped prompt the government of the then UK prime minister Harold Wilson to encourage (and fund) Russian teaching in the country's schools and universities - and is one reason why I, and other Britons of my generation, had the opportunity to study Russian. Today the challenge, the excitement, and to some the perceived threat comes from a rising China - and now not just on planet Earth.
An open question is how far China will be welcomed - or not - into the existing space "club". After the no-holds-barred space rivalry of the US and the Soviet Union that constituted a part of the cold war, the US and Russia have settled into a more collaborative relationship in space that has largely withstood the worst of diplomatic tensions.
The US suspended its space shuttle program in 2011, but it has continued to send astronauts into space using Russian rockets, and the International Space Station has remained in use as a shared venture. Diplomatic expulsions, accusations of election interference and terrestrial disputes most recently over Ukraine and Syria have not affected cooperation in pursuit of national scientific and security interests in space. Space has remained a sanctions-free zone.
It has taken more than half a century for US-Russia space cooperation to reach this point of relative equanimity, but the arrival of China as a serious player - graphically illustrated by its latest success - has the potential to disturb this. Will Russia, for instance, see China, with its recent successes and innovations, as a future partner in space or a deadly rival?
The US - through its long-Sinophobic Congress - seems already to have made up its mind. Not only is it increasingly treating China as an economic and military competitor, but US President Donald Trump recently ordered the creation of a new Space Command for the US armed services, suggesting the direction of his thinking here, too.
So far, China's precise ambitions for its space program remain unclear. Establishing itself as a space power is surely one - but is it as a space power, or the space power?
The equipment it has now sent to the moon suggests that communications and new natural resources are priorities. How far will the US, in particular, be prepared to watch and wait while Beijing potentially races ahead in these sensitive areas? Stand by for the US and Russia to take a new interest in the moon.
The writer is a noted columnist
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