The Chinese military shot down one of its own aging satellites with a ground-based ballistic missile last week, demonstrating a new technological capability at a time of growing Bush administration concern over Beijing's military modernization and its intentions in space.
The shoot-down, which U.S. officials said occurred on the evening of Jan. 11, prompted a formal protest from Washington that was joined by allies including Canada and Australia, U.S. officials said Thursday. Japan has demanded an explanation, and Britain and South Korea are also expected to file formal objections.
"The United States believes China's development and testing of such weapons is inconsistent with the spirit of cooperation that both countries aspire to in the civil space area," said Gordon D. Johndroe, spokesman for the National Security Council. "We and other countries have expressed our concern to the Chinese."
A spokesman for China's Foreign Ministry said today that he could not comment on the anti-satellite test.
The U.S. and the Soviet Union each conducted similar tests of anti-satellite weapons in the 1980s, but abandoned the practice when the strikes led to widespread debris fields in space that threatened other satellites. The last U.S. test was in 1985.
According to U.S. officials, Beijing used a medium-range missile to shoot at its weather satellite, which was 537 miles above Earth when it was hit. The altitude is considered to be a low Earth orbit, but represents the band where most satellites and manned space missions travel.
The successful exercise was expected to send tremors through the U.S. satellite industry, which is part of a $90-billion global business involving hundreds of orbiting craft that are essential to routine daily communications and commerce. Many ATM and pay-at-the-pump transactions rely on satellites, as do television and digital radio signal distribution.
The shoot-down has rattled U.S. defense officials, who are concerned both about the commercial crafts and government spy and military satellites that operate at that height.
Larger telecommunications satellites and certain military satellites that provide early warning of missile launches travel in much higher orbits -- up to 23,000 miles above Earth.
The Chinese strike on the satellite launched in 1999 was first reported by the aerospace trade magazine Aviation Week & Space Technology.
Concerns about rising threats to U.S. satellites led the Bush administration to issue a new national space policy in August, which held that the U.S. viewed freedom of action in space as important as air or sea power.
The administration was widely criticized for its aggressive attitude toward defense activities in space. But a White House official, speaking on condition of anonymity, said Thursday that satellites and access to space were considered vital to U.S. national and economic security and that any event "that can hinder passage through space" was of concern.
News of the Chinese achievement came as John D. Negroponte, the head of U.S. intelligence agencies, testified before the House Intelligence Committee on a range of international threats, including what he said were the potential dangers of China's military buildup.
"The Chinese are developing more capable long-range conventional strike systems, and short and medium-range ballistic missiles with terminally guided maneuverable warheads able to attack U.S. carriers and air bases," Negroponte said in his testimony.
China has stepped up both its civilian and military space program in recent years. In October 2003, it became only the third nation, after Russia and the U.S., to launch its own manned space mission.
U.S. intelligence and military officials have become increasingly vocal over Chinese ambitions in space and over Beijing's military modernization program, begun in 1999. Senior Pentagon officials have urged the Chinese to explain the motives behind their buildup, saying the lack of clarity has fueled concerns that their new weapons might be used against the U.S.
Officials also have voiced concerns that, because the U.S. is so dependent on satellites, militarily and commercially, an inability to protect its space assets would represent a vulnerability that adversaries could exploit.
"We must be very concerned about the emerging threats to our space assets and about the possibility that others will take advantage of our dependence on and vulnerability in space to seek asymmetrical advantages over us," Robert G. Joseph, the State Department's top arms control official, said in a speech last week.
China's leaders are intent on modernizing their military capabilities, and the development of more sophisticated weaponry, including anti-satellite missile capabilities, is part of that effort, said Shi Yinhong, a professor of international relations at People's University in Beijing.
But he said China was still at least a decade behind several other countries.
"Generally speaking, China's military capability in these advanced areas, whether it's space weaponry or naval capabilities, is still far behind the United States and Japan," he said. "What you are seeing is new momentum to try and catch up, but the distance is still quite wide."
Shi said he understood why leaders in the U.S. and elsewhere might view China's anti-satellite test with alarm, but that the move represented a natural development and was not intended to provoke an arms race in space.
The new American space policy holds that the U.S. retains the right to take any action necessary to protect its space assets and to prevent adversaries from using "space capabilities hostile to U.S. national interests."
China's space modernization effort is part of a campaign to defend itself against the U.S. government's missile defense program, which officials in Beijing view as a militarization of outer space, said Wenran Jiang, head of the China studies program at Canada's University of Alberta.
He said Chinese military leaders were paying particular attention to Washington's information warfare efforts, including the development of sophisticated weaponry to "destabilize the enemy's communications and control systems."
Pentagon officials rebutted allegations that the new policy attempted to militarize space, saying that the ability of U.S. adversaries to cripple military and commercial satellites posed a serious threat for which the military was not yet prepared.
"I'm not talking about weapons of mass destruction" in space, said a senior Pentagon official, who spoke on condition of anonymity when discussing internal debates over military space policy. "I'm talking about what's the next step if somebody whacks a satellite? Do we just go out with a bullhorn and express our outrage?"
Despite objections to putting weapons in space, American military officials are concerned that they will be blamed for inaction if they fail to prevent an attack on U.S. satellites.
"We need to be able to know who's messing with our satellites -- not just our military ones, but our commercial ones," said another senior Pentagon official. "If something's affected, they're going to call [and ask], 'What are you going to do about it?' "
China provoked widespread concern in September after it used a ground-based laser to illuminate at least one U.S. satellite. The action was confirmed by the U.S. National Reconnaissance Office, the intelligence agency that oversees spy satellites. The Pentagon has warned of intelligence that shows China is developing a laser system to blind or damage imaging satellites.
Among U.S. satellite operators, word of China's latest anti-satellite test was greeted warily.
"We're concerned, but we haven't gotten a lot of calls from our customers so far," said Arnold Friedman, senior vice president for Space Systems Loral of Palo Alto, which operates 53 satellites in orbit. "We're always concerned whenever anything of that sort happens."
Most of Loral's satellites would be out of reach to the type of missile used by the Chinese because they orbit about 23,000 miles above the Earth.
Other satellite executives declined to comment or referred questions to the Pentagon.
Times staff writers John Johnson Jr. in Los Angeles and Evelyn Iritani in Beijing contributed to this report.