The image of a Navy missile fired from the Pearl Harbor cruiser USS Lake Erie streaking into outer space to obliterate a failing U.S. spy satellite boosts the credibility of the nation's missile-defense system.

That was the view of U.S. Defense Secretary Robert Gates, who was in Hawai'i yesterday as part of a nine-day trip that includes Australia, Indonesia, India and Turkey.

The satellite was passing 130 miles above the Pacific on Wednesday when the interceptor missile hit it.

"We've had a number of successful tests," Gates said, "and I think the fact that the Congress pretty much overwhelmingly the last two or three years has voted billions of dollars to continue with the missile-defense program (says it is working) and we just need to keep improving its capability."

Gates spoke after visiting the destroyer USS Russell in Pearl Harbor, which was on standby for the satellite shootdown.

The Bush administration has spent about $10 billion a year on missile defense in recent years.

A network of radars tracked the satellite and helped aim the intercepting missile. The network included the Sea-Based X-Band Radar, the giant floating "golf ball" that was in Hawai'i recently for repairs.

The falling satellite was shot down because of the possibility that its toxic fuel could land in a populated area, the Navy said.

The satellite was moving faster and higher than the missiles that had previously been used as targets in Navy tests.

"It did confirm the ability of the SM-3 to intercept at a higher elevation," said Baker Spring, a specialist at the Heritage Foundation think tank and a longtime advocate of missile defenses.

CHINA DISPLEASED

A skeptic of U.S. intentions over the satellite shootdown was China, which raised concerns before and after the fact.

Yesterday, the Beijing government asked the U.S. to release data on the shootdown, and the Communist Party's newspaper blasted what it called Washington's callous attitude toward the weaponization of space.

Asked about China's concerns, Gates told reporters during a visit to U.S. Pacific Command at Camp Smith that the United States is prepared to share with China some of the information about the shootdown, but he was not specific. He said some was provided beforehand.

China drew strong U.S. condemnation last year when it downed one of its own weather satellites in a test, creating a large amount of space debris.

The Pentagon said yesterday's U.S. shootdown was timed to minimize the amount of debris that would remain outside the atmosphere.

By 2009, three U.S. cruisers and 15 destroyers are expected to have the capability to intercept short- and medium-range ballistic missiles. Most of the ships will be based in the Pacific. Land-based interceptors also are being tested.

The Pearl Harbor destroyers Russell and Hopper, and cruisers Lake Erie and Port Royal, already have the shoot-down capability. Testing continues off Kaua'i.

In a November test, two target missiles were launched from the Pacific Missile Range Facility at Barking Sands.

SATELLITES EASIER TO HIT

The Lake Erie's Aegis weapons system detected and tracked the targets. About two minutes later, Lake Erie's crew fired two SM-3 missiles, and two minutes after that, they intercepted the targets outside the Earth's atmosphere more than 100 miles above the Pacific Ocean and 250 miles northwest of Kaua'i.

Shooting down ballistic missiles is more complex than shooting down satellites, which move on a relatively predictable path.

That helps explain why the United States has chosen not to field an arsenal of anti-satellite weapons: there is the risk of inviting retaliation against vulnerable U.S. satellites, which are vital to national and economic security.

The Pentagon had shown decades ago that it could smash an orbiting satellite. This week's strike showed that it could be done with an array of missiles, radars and command systems that at times have failed to perform in tests against long-range ballistic missiles.

In Wednesday's shootdown, a Navy SM-3 missile launched from the Lake Erie cruising northwest of Hawai'i not only hit the satellite but apparently struck precisely where its operators had aimed: a titanium-encased tank of hydrazine fuel that officials said could pose a health hazard to humans on re-entry.

Henry Cooper, who was the Pentagon's "Star Wars" chief from 1990 to 1993, said the outcome bodes well for the Navy and prospects for adding to its missile defense repertoire.

The Lake Erie, which is returning to Pearl Harbor this morning after Wednesday's shootdown, has been used for testing the Aegis ballistic missile defense off Kaua'i and in November registered the 10th and 11th successful intercepts out of 13 targets.

"It (the satellite success) is definitely a boost for the Navy program because everybody is made aware of the flexibility and perhaps even the reliability of the program," Cooper said in a telephone interview.

At the Pentagon, Marine Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, told reporters it would be wrong to think that the satellite shootdown was done to demonstrate that the U.S. military has an anti-satellite capability.

"We understand ASAT," Cartwright said, using the military's acronym for anti-satellite weaponry. "There's no reason to go back and re-prove what we've already done."

Three specially-modified SM-3 missiles were available for the shootdown. The USS Decatur, a destroyer out of San Diego, was at sea, while the Russell remained in port.

"We were here in case anything went wrong," said Ensign Jason Garfield, the Russell's first lieutenant.

Its SPY-1 radar system was not turned on, officials said.

The Russell's commanding officer, Cmdr. Jeff Weston, said the strategy was to have three ships with ballistic missile capability ready to participate in the shootdown.

The Russell can perform air defense as well as ballistic missile defense, Weston said.

"I think it (the ballistic missile capability) is an absolutely fabulous system, and it can deliver," Weston said.

"We are trained, the crew is just amazing. ... If we were asked to defend Hawai'i, I believe we can clearly do it. I feel very confident."