U.S. government officials and defense experts showed little confidence in the missile defense system which has cost the Bush administration 43 billion U.S. dollars so far, a newspaper report said on Thursday.

The system would either be hit or miss incoming missiles in case of an emergency, the Los Angeles Times reported.

The system has not undergone a successful test in nearly four years and have been beset by glitches that investigators blame, at least in part, on President George W. Bush's order in 2002 to make the program operational even before it had been fully tested, said the report.

Since Bush took office in 2001, he has pushed the ballistic missile defense system despite a controversy over the program designed to down enemy missiles in various stages of flight.

The U.S. has 11 ground-based interceptors in Alaska and at Vandenberg Air Force Base in Central California, the cornerstone of the administration's new system. In all, the interceptors hit dummy missiles in five out of 10 tests, but these were under controlled conditions that critics say do not reflect the challenges of an actual missile launch.

The Government Accountability Office (GAO) said in March that program officials were so concerned with potential flaws in the first nine interceptors now in operation that they considered taking them out of their silos and returning them to the manufacturer for "disassembly and remanufacture."

"Quality control procedures may not have been rigorous enough to ensure that unreliable parts, or parts that were inappropriate for space applications, would be removed from the manufacturing process," the office said in a notice.

"The problems in the ground-based system, as well as the ongoing expense of the war in Iraq, have not damped the administration's enthusiasm for the program," the paper said.

The Pentagon has requested 10.4 billion dollars for missile defense in next year's budget, which would be its largest annual grant to date. And according to the GAO, the Pentagon plans to spend 58 billion dollars, or 14 percent of its research budget, on missile defense over the next six years.

Source: Xinhua