‘Star Wars’ Enters Second Decade With No Hardware, $30-Billion Tab : Defense: Debate over its future centers on its scope. The objectives continue to change drastically from Reagan’s.

Ten years ago Tuesday, former President Ronald Reagan delivered his “Star Wars” speech to launch a massive research effort to make nuclear weapons “impotent and obsolete.”

Since then, the program has cost close to $30 billion, produced a dizzying array of blueprints for missile defenses and has taken political and bureaucratic hold in Washington. Yet not a single new missile defense weapon has been deployed.

Today, on the threshold of its second decade, the objectives of the Strategic Defense Initiative are as different from those of 1983 as the balance of power in the world--and the nuclear threats to U.S. interests--are from the days of Reagan’s first term.

Proponents say they believe that SDI has achieved Reagan’s visionary goal even without the hardware. In recent years, they observe, the nuclear superpowers have been agreeing to shed nuclear weapons as if they had become “impotent and obsolete.”

But debate still swirls around “Star Wars,” the most controversial Pentagon initiative of the nuclear era. And despite the election of a Democratic President who promised to bring “a healthy dose of reality” to the effort and the wishes of SDI’s harshest critics, the arguments these days are over the scope of the program--not whether it should exist.

The Clinton Administration has given an early indication that rather than change course, it may accept the previous Administration’s broader--and more expensive--goal of providing a national missile defense.

Internal budget planning documents propose a budget of roughly $16 billion over the next four years. That budget was designed to allow the deployment of a national missile defense around the year 2002.

Under Defense Secretary Les Aspin, the Pentagon has launched a major review to determine whether the program should aim to build a network of defenses to protect the entire United States or should focus more narrowly on providing missile defenses for troops in combat theaters.

Unquestionably, “Star Wars” already has greatly distanced itself from the vision Reagan described in his speech of “a shield that missiles could not penetrate--a shield that could protect us from nuclear missiles just as a roof protects a family from rain.”

In its earliest incarnations, “Star Wars” was dogged by debates of almost theological dimensions. Controversy over the cost and feasibility of the program belied a more intense debate over the wisdom of replacing a doctrine of “mutual assured destruction”--the cornerstone of nuclear deterrence--with a reliance on missile defenses.

With a U.S. missile shield deployed, some nuclear theorists surmised, Soviet leaders would fear that the United States could boldly launch a nuclear attack, confident it could shield itself from the resulting counterattack.

In the arcane logic of nuclear deterrence, such a calculation could encourage the Soviet Union, either before the missile shield was deployed or in a time of crisis, to mount a surprise first strike in hopes of beating the U.S. defenses.

Disputes over the effectiveness of any missile shield played into these debates. If the defense were imperfect or could be overwhelmed easily, the deterrent effect of nuclear weapons could break down further, theorists reasoned. The Soviets would recognize that if they launched a determined first strike, it might be able to punch through the defenses.

Because the defenses might give one side an incentive to strike first, the U.S. arms control community pronounced missile defenses destabilizing and dangerous.

By 1988, the prospects for Reagan’s SDI were being undermined by persistent questions about the wisdom of the program, the nation’s ability to actually develop it and the cost--calculated by some independent analysts to be as high as $770 billion.

Then-President George Bush ordered work on a phased approach, bringing the cost for a rudimentary defense system to about $70 billion. By then, the perceived effectiveness of the system was also being undermined by a series of failed tests of new defensive technologies.

In January, 1988, Sen. Sam Nunn (D-Ga.), the influential chairman of the Senate Armed Services Committee, proposed to scrap development of the global missile shield and focus on building a more limited, cheaper system designed to defend the nation against accidental or unauthorized missile strikes.

With the Cold War waning, the prospect of such a smaller missile attack had grown far greater than an all-out strike from the Soviet Union, Nunn said.

His proposal proved prophetic, as the Warsaw Pact and then the Soviet Union unraveled over the next three years. It also provided “Star Wars” with a strategy for political survival at a time of declining defense budgets and mounting skepticism about the program’s claims.

With the Soviet Union coming apart and the Persian Gulf War about to begin, Bush embraced Nunn’s proposal in January, 1991, and announced a shift away from a global defense to a more limited system aimed at protecting against accidental missile strikes.

Along the way, the system evolved from Reagan’s vision of an orbiting space umbrella of laser-firing weapons to a ground-based network of defense missiles, augmented by orbiting elements.

Within weeks of Bush’s remarks, Americans watched as Iraqi Scud missiles careened toward Saudi and Israeli cities and toward U.S. troop concentrations in the Saudi desert.

Here, said many politicians, was evidence that missiles continued to threaten Americans at home and abroad. Here also was a weapon--the Patriot missile--that appeared capable of the tricky task of defense against such threats.

By November, Congress adopted the Missile Defense Act of 1991, calling on the government to deploy an anti-ballistic missile system.

“Since the demise of the Soviet Union and the Gulf War, the old ways of thinking about how to maintain nuclear stability in the world . . . are just gone,” said Edward T. Gerry, the Pentagon official who now serves as the SDI’s system architect.

When the missile act passed, “it was clear that things were very different,” Gerry said. “No such thing had ever happened before. The word ‘deploy’ was something you’d never seen out of Capitol Hill.”

The program has also been buoyed by Third World powers that have been trying to develop nuclear warheads and missiles to deliver them.

Indeed, in 1993--the year Reagan envisioned a decision being made to deploy his system--few can be heard arguing to abandon the idea outright.

Clinton has called for some reductions in the program’s budget. Bush proposed to seek $6 billion for the program in 1994--a figure that Clinton is expected to trim to roughly $4 billion for next year.

Many lawmakers are expected to call for deeper cuts, but only Sens. Jim Sasser (D-Tenn.) and Dale Bumpers (D-Ark.) have continued to fight the basic orientation of the program--the imminent deployment of missile defenses. That goal, they maintain, adds at least $2 billion each year to the program’s budget.

“SDI will not protect the United States against bombers, will not protect us against cruise missiles . . . and it certainly is not going to protect us against terrorists like the guy in New York” alleged to have had a role in the bombing of the World Trade Center, Bumpers said in a speech earlier this month.

“For the past few years, some of us in Congress have waged what often seems like an uphill fight to cut funding for large parts of the SDI program and to limit deployments,” Sasser said. “But I think each year, a few more recognize the folly of this spending and recognize that the threat is not there to justify it.”

For the first time since Reagan described his hope for a space-based shield, however, Sasser sees real hope of an ally in the White House.

“Now, we have a defense secretary and President who seem to recognize we cannot fund every exotic weapons program that comes along. Maybe this year.”