When the United States raises the prospect that it will build a missile defense system, Russian strategic planners don't have far to go for a response.

They can reach for a drawer marked "Star Wars" and take out some of the Soviet-era blueprints drawn up more than 15 years ago in response to President Reagan's grand hopes for the Strategic Defense Initiative, a missile defense shield.

There, gathering dust until recently, are some choice ideas and gadgets that the Soviet designers thought could be used to confuse, evade, saturate and overwhelm a missile defense system.

Reagan never realized his vision of a global shield against ballistic missiles, and the Soviet ideas were mostly laid to rest, in some cases by subsequent arms control treaties. But in recent weeks, Russia's top military strategists have begun to trot them out again, and they are openly promising to reanimate these schemes if necessary to frustrate an American missile defense system.

These include the use of decoy warheads, space-based "chaff" to simulate warheads, maneuverable warheads to steer away from interceptor rockets and prolonging the deployment of huge land-based, multiple-warhead missiles.

The Clinton administration has said it will not decide until June whether to go ahead with a limited missile defense, requiring changes in the 1972 Anti-Ballistic Missile Treaty. Russia, which opposes treaty modifications, has already ratcheted up a noisy campaign against changes, saying they would destroy all arms control efforts of the last 20 years and wreck such cooperative efforts as reciprocal inspections.

The result has been a back-to-the-future scenario in which Russia is reviving gambits dreamed up in the Soviet era to fend off a missile defense system like that dreamed up in 1983 by the Reagan administration.

An antimissile system uses a combination of detectors like radar and satellites to spot incoming missiles and warheads and then deploys fast-flying interceptor rockets to try to destroy them before they land or explode. At the center of the old Soviet ideas now being refloated is to defeat the missile defense system by fooling it.

The pride of the Russian Strategic Rocket Forces is the relatively new Topol-M, a solid-fuel missile, now carrying a single warhead, which was designed to replace older, multiple-warhead missiles being retired under arms control treaties. Russia put a regiment of 10 Topol-M missiles on duty last year, and is expected to deploy a second regiment by the end of next month.

But Russian officials have said they could convert the Topol-M into a three-warhead missile. Such multiple-warhead land-based missiles were outlawed by the START II treaty, which has never been ratified by the Russian parliament and may not be. Moreover, Russians have said the START I treaty could also be endangered.

"If this [antimissile] treaty crashes, then there are no problems to increase the launched weight of the rockets," Maj. Gen. Vladimir Dvorkin, director of the Defense Ministry's Central Research Institute and a leading strategist, said in a recent newspaper essay.

The added launch weight is to accommodate additional warheads or other equipment to defeat an antimissile system. Russian specialists said the Topol-M could carry at least three and perhaps as many as six warheads. Yuri Solomonov, director of the Moscow institute that designed the Topol-M, said earlier this year that it could "penetrate any country's antimissile system."

Sergei Rogov, director of the Institute for the Study of the United States and Canada, and a top Russian arms control expert, said that Russia has numerous ways to try to defeat an antimissile system with "penetration aids," such as decoy warheads.

Moreover, Russia has the ability, developed in the Soviet era, to deploy a kind of chaff, or deceptive particles, in the nose cone of the Topol-M. When released, the chaff "will look like thousands of warheads" to the missile defense system, he said, and it will be difficult to distinguish the real from the fake.

Yet another attribute of the Topol-M, specialists said, is that it has a maneuverable warhead, which can change direction after being released from the missile to try to evade interceptor rockets. The maneuverable warhead was tested in Russia last summer. The Topol-M also has a shorter engine-burn time to minimize satellite detection on launch.

Russia also recently announced it intends to resume production of its most modern submarine-based multiple-warhead missile, the SS-N-23. While deployed with four warheads each, Russian officials said it was originally tested with 10 warheads, and might be restored to that number. The warheads were scaled down for the START I treaty. Dvorkin suggested that some of these liquid-fuel missiles could be deployed on land, as well, if the treaties are torn up.

Dvorkin has also suggested Russia would again put its rail-mobile land-based missiles, which have been parked, back on patrol.

Rogov said there were other measures. "You can attack the defenses," he said, with such devices as nuclear explosions in space, or by targeting the brain center of the missile defense system.

Moreover, Dvorkin said, Russia could simply stretch out the multiple-warhead missiles now due for retirement under arms control treaties.

Dvorkin and others have insisted that Russia can afford these measures, despite its chronic financial troubles. But others have questioned how far Russia can really go to carry out its threats. The Topol-M has been underfunded and years behind the original schedule.

Alexander Pikayev of the Carnegie Endowment for International Peace noted that until recently the Russian nuclear forces had received most funding for procurement. But, he said, the balance is changing and more money is being allocated for conventional weapons procurement.

Defense Minister Igor Sergeyev, a former rocket forces chief, has long advocated special treatment for the nuclear forces, but Sergeyev's tenure may not outlast President Boris Yeltsin, who leaves office next year.