Something remarkable has occurred during the five years since President Reagan announced his vision of an America protected from nuclear attack by a futuristic space-based missile defense.
Reagan's dream, widely ridiculed then as Hollywood-inspired "Star Wars," a Technicolor fantasy, has become an undeniable and at least temporarily irreversible part of American reality.
It was in a March 23, 1983, speech that Reagan called on the nation's scientists to devise a defensive system that would make nuclear weapons "impotent and obsolete." They have not yet met that challenge, and they generally agree that Reagan's dream of a leak-proof "Astrodome" against nuclear missiles is impossible.
Offers Some Protection
Yet the Defense Department, under authority from a Democratic-controlled Congress, is planning and testing a scaled-down system that offers to protect at least some places in the United States from some Soviet missiles.
The Strategic Defense Initiative, as the system is formally known, has been enshrined in a $4.6-billion-a-year Pentagon bureaucracy and has gathered enough political momentum that even this year's Democratic presidential candidates are threatening to do no more than scale it back.
"Politically, the issue is here to stay," conceded House Armed Services Committee Chairman Les Aspin (D-Wis.), a frequent SDI critic. "The Astrodome idea is hopeless . . . but, given the political reality, you have to have something."
Air Force Lt. Gen. James A. Abrahamson, who heads the SDI program, predicted that the next President, no matter who he is, "would not choose--no matter what their personal inclination would be--to just stop. The important thing is, the program is established as a national debate about what is the right thing to do, and we are making technical progress."
But the defense that Pentagon planners and dozens of outside contractors have already spent $14 billion working on is vastly smaller and less ambitious than the impermeable space shield based on far-out new weapons that Reagan envisioned.
Gone for the foreseeable future are the exotic electromagnetic rail guns firing rocket-smashing projectiles, the space-based neutral particle beam weapons, the ultra-high-power free-electron lasers. Research on these advanced technologies will continue, but development of workable systems is impossible in this century, perhaps ever, planners say.
Instead, the Pentagon is now devoting almost half its yearly SDI budget to working on a limited "Phase 1" defense that would, at best, be able to intercept one-fourth of incoming Soviet intercontinental ballistic missiles. Not even counting Soviet weapons on submarines and bombers, that would leave the Soviets enough ICBMs to destroy the United States several times over.
Given political support and adequate funding, defense officials say, they could put such a system in place as soon as 1996.
Limited System Defended
Pentagon officials defend the limited system as a tool to complicate the Soviet military planner's job by taking away his confidence that his missiles will reach their intended targets.
"A strategic defense need not be 'leak-proof' to achieve this objective," Defense Secretary Frank C. Carlucci told Congress earlier this year in presenting the rationale for a porous space umbrella.
Opponents charge that even the less ambitious version of SDI would turn space into a battleground. More than that, they say, it is likely to spur a new arms race as the Soviets build more missiles to overwhelm American defenses and the United States answers with new weapons to offset the Soviets'.
Reagan responds by calling nuclear defense a moral necessity. A defensive system that saves lives, he insists, is superior to offensive weapons that threaten annihilation.
It is an idea that appeals to many Americans. Some 55% of registered voters polled by the Daniel Yankelovich group in January said they approved of continued SDI research, and only 33% said they objected.
Perhaps the biggest challenge now facing the Defense Department is to field a workable system at an affordable price. Although Abrahamson and his SDI managers say they can build the pieces of a rudimentary Phase 1 system that could shoot down some Soviet missiles, they are not as confident that they can do it at a price Americans are willing to pay.
"Can you build a rocket that goes fast?" Abrahamson asked. "That's no problem. Can you build it at the right cost? That is."
With a budget of $4.6 billion this fiscal year and about the same likely next year, "Star Wars" is already the single biggest item in the Pentagon budget. If the United States decides to build the Phase 1 system starting in 1993 or 1994, SDI spending will have to rise dramatically.
Phase 1 envisions a network of 200 to 350 space-based interceptor satellites, each capable of firing about 10 "kinetic kill vehicles" or "smart rocks"--non-explosive projectiles that would destroy incoming missiles by force of impact.
Col. Raymond R. Ross, director of SDI's kinetic energy program, said his goal is to keep the price of each interceptor satellite--or "garage"--at about $50 million. The current hope is to deploy the Phase 1 system over three years after receiving the go-ahead, meaning that the Pentagon would have to put about 100 garages in orbit in each of the three years--$5 billion a year just for the hardware.
And that does not include the cost of two launches a week of expendable rockets, which have not even been developed yet, or of all the other systems involved in Phase 1--about two dozen surveillance and tracking satellites, 1,500 ground-launched interceptor missiles and several high-tech battle management centers.
Although the Pentagon will not provide its estimate of the total cost of the Phase 1 system, the Congressional Research Service said in a recent study that the Pentagon believes that Phase 1 research and development alone would cost between $75 billion and $150 billion.
$250-Billion Price Tag
Various other analysts have put the cost of actually deploying Phase 1 at about $250 billion. That means annual expenditures of about $30 billion--more than one-third of the Pentagon's entire procurement budget this year.
No matter how much the United States spends on SDI, the Soviet Union contends it can neutralize the system at a much smaller cost by building additional missiles to overwhelm the defenses or by building killer satellites to attack SDI components in space. The Soviets already have anti-satellite weapons and are building several new generations of intercontinental ballistic missiles with fast-burning engines that are hard to intercept.
"If the Americans have a lot of money, let them squander it on SDI," Soviet leader Mikhail S. Gorbachev said during last December's summit in Washington. "We will look for a response along other, asymmetrical lines that will be less expensive by a hundred times, or probably more."
SDI program officials are counting on longer-term technologies such as beam weapons and space lasers to foil some of the Soviet countermeasures. They hope that laboratory progress on such weapons will drive the Soviets to the bargaining table.
May Deter Soviets
"To the degree that such demonstrations of advanced technologies are credible and convincing, they may deter Soviet countermeasures and encourage the Soviets to seek realistic . . . reductions" in their offensive ballistic missile force, Carlucci told Congress earlier this year.
The cost of actually deploying a full-scale SDI system, complete with the exotic weapons that earned the "Star Wars" nickname, would be astronomical. In a 1987 study, Washington defense analysts Barry M. Blechman and Victor A. Utgoff said a comprehensive system, including defenses against submarine-launched missiles, cruise missiles and intercontinental bomber aircraft, could cost $770 billion to develop and deploy.
While those technologies are confined to the drawing board or the laboratory, the Pentagon has successfully tested some elements of Phase 1, including the ground-based rocket that is designed to intercept incoming Soviet warheads. But Navy Capt. John J. Donegan, project manager for Phase 1, concedes that daunting technical problems remain.
Chief among them is sensor technology--the ability of instruments in space or on the ground to track enemy missiles, distinguish them from the fiery plumes surrounding them during their boost phase and discriminate between warheads, decoys and other debris in space.
Donegan also said the United States lags in production of the advanced miniature microchips that will be needed in SDI weapons and data-processing centers. And he noted that the Pentagon is nowhere near development of a rocket to put SDI components in space.
Donegan, who oversaw development of the Navy's successful Aegis computerized shipborne battle management system, called these problems solvable, given enough time and money.
However, that is exactly what troubles many "Star Wars" foes. Arms control experts who oppose SDI say that a world in which both superpowers are vulnerable to missile attack is far safer than a world in which one side has a defensive shield behind which to launch an attack.
35 Years of 'Deterrence'
A shift to a defensive posture, they note, undercuts 35 years of "deterrence"--the theory that each superpower is inhibited from attacking the other by the certainty of a massive retaliatory strike. The doctrine is known as MAD--mutual assured destruction--a balance of terror Carlucci refers to as a "mutual suicide pact" between the United States and the Soviet Union.
In his 1983 speech, Reagan referred to MAD as "immoral" and asked: "Why don't we have MAS instead--mutual assured security?"
By his 1988 State of the Union address, however, Reagan, reflecting a shift in rhetoric echoed throughout his Administration, backed off earlier claims. Rather than billing strategic defense as an alternative to deterrence, Reagan described it as a way to "offer the world a safer, more stable basis for deterrence."
Jack Mendelsohn, deputy director of the Arms Control Assn., a private group that promotes arms control and opposes SDI, said Reagan has it backward.
"Defenses are provocative and not protective," Mendelsohn said. "(Former Defense Secretary Caspar W.) Weinberger said if we thought the Soviets were going to build defenses, we'd increase our offenses.
"The second problem with defense is it tends to drive people toward preemption, to strike first in a crisis. If you wait, you won't penetrate the defenses."
The debate over strategic defenses on all its levels--technical, fiscal, political, moral--is now a part of the American landscape. Even if the most ardent opponent of the program were to be elected President, he would find it impossible to kill SDI. There are too many votes for the program on Capitol Hill, too many multimillion-dollar, multiyear SDI contracts spread around, too many space defense careerists in the Pentagon to shut it down cold.
"Now there's a constituency for defense," said Aspin. "I don't think you can legitimately sustain a no-defense position."
When and whether a space shield will be built remains an open question. The answer depends in large measure on Soviet behavior and how much Congress is willing to spend for a partial defense.
"What we offer is a possibility," said Air Force Col. Garry A. Schnelzer, the SDI program's acting director of technology. "It's up to the decision makers of this country to decide whether they want it."
Star Wars: Five Years Later
Phase I of President Reagan's Strategic Defense initiative, the only phase even remotely on the horizon, would employ self-guided projectiles of about 20 pounds-- "smart rocks"--that would demolish Soviet offensive missiles and warheads on impact. Some elements of Phase I components are in the testing phase; others remain on the drawing board. The Defense Department intends to decide in about 1933 whether to proceed with Phase I to deployment. The system could not be operational before 1996. Listed below are various elements of Phase I.
1. Boost Surveillance and Tracking System (BSTS)
About 6 reconnaissance satellites to detect Soviet missiles during the 5-minute boost phase when the missile rockets are burning.
Contractors: Lockheed Missiles and Space Co.; Grumman Corp.
2. Space-Based Interceptors (SBI)
200 to 350 satellites housing rocket-propelled "smart rocks" of about 20 pounds that, by force of impact, destroy enemy missiles in boost phase and warheads in mid-course phase.
Contractors: Rockwell International; Martin-Marietta
3. Space-Based Surveillance and Tracking System (SSTS)
About 20 reconnaissance satellites to track Soviet missile warheads during their mid-course phase.
Contractors: Lockheed; TRW Electronics and Defense Sector
4. Ground-Based Surveillance and Tracking System (GSTS)
30-40 ground-launched missiles to track incoming enemy warheads in mid-course phase and when warheads enter the atmosphere.
Contractors: McDonnell Douglas Aeronautics; Science Applications International
5. Exoatmospheric Reentry Vehicle Interceptor Subsystem (ERIS)
As many as 1,500 ground-launched rockets that destroy enemy warheads in mid-course phase.
Battle Management/Command, Control, Communications (BM/C3)
Computerized ground command and communications center to collect and process data from tracking systems and make assignments to space-and ground-based weapons.
Contractors: TRW; IBM Federal Systems Division; McDonnell Douglas; Ford Aerospace and Communications.