‘Star Wars’ Not Perfect, Weinberger Says : He Sees Lack of Fail-Safe System but Stresses Population Shield

Defense Secretary Caspar W. Weinberger held out the likelihood Tuesday that if the Reagan Administration proceeds with its so-called “Star Wars” project, the missile defense system would be deployed without a guarantee that it would halt all incoming missiles.

“We wouldn’t say ‘We won’t deploy’ because we can’t give you a guarantee that everything will always be perfect,” Weinberger said in a breakfast session with reporters.

In unveiling the program thre e years ago, President Reagan portrayed it, formally known as the Strategic Defense Initiative, as a shield-like network that would leave the United States safe from missile attack.

Remains Overall Goal

Weinberger insisted that the Administration has not wavered from its overall goal of erecting such a system to protect the nation.

Indeed, Weinberger took pains to emphasize repeatedly that the system, if deployed, would be intended to protect more than just the nation’s own intercontinental missiles and their launchers--a so-called “site defense” that was the heart of the anti-ballistic missile system abandoned by the United States more than a decade ago.

He declared: “We’re not interested in site defense. We’re not interested in protecting the missiles. We’re interested in protecting the people. We’re not trying to protect any target in the United States.”

However, a senior Pentagon official, speaking on the condition that he not be identified by name, later said that a limited shield protecting the offensive missiles could be a valuable deterrent. An attacking nation thus could not be certain that a surprise “first strike” would destroy the United States’ ability to launch a retaliatory attack, he explained.

Missile Defense Key Role

As conceived by the Administration, the primary goal of the system would be to destroy enemy missiles as they blasted out of silos or as they emerged from the “boost” phase that lifts them out of the atmosphere. But subsequent “layers” would be designed to intercept warheads that had separated from missiles and were heading toward targets within the United States.

Despite Weinberger’s view, others within the Pentagon, including Assistant Defense Secretary Richard N. Perle, have been quoted as saying that the initial role for such “layers” is in protecting the nation’s retaliatory ability rather than the population.

John Pike, a space policy expert for the Federation of American Scientists and a frequent critic of the missile defense plan, said Weinberger’s emphasis on wide-area defense reflected “one of the real dilemmas the program faces.”

Referring to Perle’s previous remarks, Pike said that in Washington the program is seen as a deterrent to nuclear attack, while outside the nation’s capital its popularity is tied to whatever potential it holds for protecting the population.

Cost Put at $1 Trillion

The initial phase of the program, for which the Administration has earmarked $26 billion, is devoted to research to determine whether a strategic defense system is feasible. Experts have produced a wide variety of estimates of the cost of building and deploying the total system, with some predicting a price of at least $1 trillion.

For fiscal 1987, which begins Oct. 1, the Administration has sought $4.8 billion for the project--an increase of about $2 billion over current funding. A Senate Armed Services subcommittee has trimmed the request to $4.1 billion, and further cuts are expected before the funding is granted.