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China has been forced to acknowledge that it has tested a new anti-satellite weapon, following protests by the United States, Japan, Australia and others.
A foreign ministry spokesman in Beijing gave a bland assurance that the test, in which US intelligence officials say a ballistic missile launched from China destroyed an ageing Chinese weather satellite on January 11, posed no threat.
But other countries, particularly US allies, are worried. The test has set alarm bells ringing in the Asia-Pacific region, where satellites play an important role in civilian communications and perform an irreplaceable service for military forces.
Last August, the US said one of its satellites had been illuminated by a ground-based laser in China, a possible first step to using powerful energy beams to destroy spacecraft. Washington did not make any formal protest then, but has now voiced concern about the Chinese hit-to-destroy missile launch.
Part of China's military modernisation programme - the most secretive part - is intended to develop weapon systems that could degrade, or even cripple, the fighting ability of more powerful adversaries.
The US military is dependent on satellites and space networks for surveillance, intelligence gathering, weapons guidance and communications. America owns or operates 443 of the 845 military and civilian satellites that orbit the planet, or slightly over half. Russia controls 11 per cent and the rest of the world 34 per cent. China owns just 4 per cent.
By shooting down one of its weather satellites orbiting about 870km above the Earth, China showed it can bring within range more than 300 satellites owned and operated by other governments and companies, including dozens of military intelligence and imaging reconnaissance orbiters.
The latter belong to a number of countries, including the US, Russia, France, Israel, Japan, India, Taiwan, and Australia. These low satellites typically have altitudes of between 80km and 2000km. In addition to spy satellites, weather and environmental orbiters also operate at this level, providing important civilian and economic services.
Commercial and military communications satellites, and US and Russian satellites providing early warning of ballistic missiles launches, usually operate much further out in space, at altitudes of around 36,000km.
This is where voice and data telecommunication satellites owned by many Asia-Pacific nations are positioned, far above the low orbit segment affected by the Chinese test.
But in obliterating its obsolete satellite, China created thousands of pieces of high-speed debris. While many would be tiny, some would be large enough to cause serious damage if they hit other satellites.
The US and the former Soviet Union tested anti-satellite technology in the 1980s, and the US shot down one of its orbiting satellites in 1985. Partly out of concern at the impact of space junk, they stopped the programmes. Washington and Moscow feared the destruction of a satellite by debris could cause the other side to conclude that a nuclear attack was about to occur.
Why then would China want to risk reviving such Cold War suspicions with a secretive anti-satellite test of its own? Washington and Tokyo will argue it shows China's ambitions for military superpower status.
Beijing may, indeed, be warning it will challenge US primacy in space-based military assets. But a more likely immediate motivation is to prod the Bush Administration, and any Democratic successor, to negotiate a treaty to ban all space weapons and the use of force against objects in orbit.
China and Russia have advocated such a treaty, arguing that it is needed to prevent a dangerously destabilising and costly arms race in space. At present, only weapons of mass destruction are prohibited in space. President George W. Bush rejected the Chinese and Russian arguments when he approved an updated US policy last year that asserted America's right to defend itself in space against any actions it considers hostile. He may find it hard to continue saying no.
* Michael Richardson is a security specialist at the Institute of South East Asian Studies in Singapore.
