Insider : Missile Minuet: Changing the Tune on Arms Control : To ban or not to ban? The answer may owe less to facts and figures than to politics and personalities.

Twenty years ago, the United States said no to banning missiles that carry more than one warhead. Ten years ago, it refused to ban mobile missiles that ride around in rail cars or trucks. But now it wants to do both in combination: ban multiple-warhead missiles that are mobile.

The Bush Administration first explored the idea about a year ago. It put the idea aside then, largely because of opposition from Defense Secretary Dick Cheney.

But two months ago, with agreement with the Soviets looming in the strategic arms reduction talks (START), the proposal’s champions revived it. Proponents argued that the proposal would be welcomed in Congress and particularly in the Senate, which would have to ratify a START treaty. Cheney’s opposition waned as the need mounted to cut the defense budget.

So last month, in a letter to Soviet President Mikhail S. Gorbachev, Bush proposed banning land-based missiles that carry more than one warhead.

The proposal was rejected. The Soviets, who have a huge arsenal of the kinds of missiles that would be banned, promptly labeled it unbalanced. Gorbachev, already facing an economic crisis at home and a secession attempt by Baltic nations, said in effect: “Go away; don’t complicate my life.” Moscow also reneged on other START issues, perhaps to show its displeasure with the last-minute U.S. proposal.

Now, there is less likelihood of completing a START treaty this year than there was before the United States launched its proposal. Arms control experts are split over whether the U.S. proposal is at least partly responsible. But no one can say for sure that it is not.

Missiles that carry more than one warhead, each aimed at a different target, became the vogue at the Pentagon in the 1960s because they offered “more bang for the buck.” Ten warheads on ten missiles cost two to three times more than 10 warheads on one missile.

The Soviets lagged in technology for multiple warheads, so in the first arms control talks in 1969, they sought to ban them. The United States refused, chiefly because it needed a surfeit of warheads to saturate and penetrate Soviet anti-missile defenses.

Mobile missiles became an issue toward the end of the 1970s, when the Soviets wanted to ban them, their goal being to stop the U.S. program to develop the 10-warhead MX missile. Each MX was to be shuttled among 23 protective shelters in a controversial “shell game” scheme.

President Jimmy Carter, rejecting the Soviet position, argued that the mobile MX would add stability to the nuclear balance. Moving around, mobile missiles are relatively secure from surprise attack, thus less likely to be fired prematurely in time of crisis, when generals might fear that they had to “use them or lose them” to an enemy attack.

But President Ronald Reagan, when he took office in 1981, worried that it would be difficult to verify Soviet compliance with a treaty limiting mobile missiles, which would be relatively easy to hide. So in the START talks, he called for banning mobile land-based missiles.

This time, however, the Soviets said nyet. They were far along on the rail-mobile SS-24 missile, which carries 10 warheads, and the smaller, road-mobile SS-25, which carries a single warhead. The United States had comparable systems--the 10-warhead MX and a single-warhead Midgetman--but only on paper.

Enter George Bush at the White House, along with a new supporting cast.

Brent Scowcroft, Bush’s national security adviser, opposed fixed-base, multiple-warhead missiles because they invite a surprise attack. They are particularly dangerous, he said, because an enemy can knock out 10 warheads with only one or two of his own. He pressed for the Midgetman, a mobile, single-warhead missile that would roam the countryside on a truck-like vehicle.

The Defense Department preferred the bigger, 10-warhead MX to move around on rails, a much cheaper system. Refusing to choose between them, the Administration proposed building both the MX and the Midgetman.

Senate Armed Services Committee Chairman Sam Nunn (D-Ga.) warned that Congress would not let the Administration build either unless it offered to ban mobile multiple-warhead missiles--that is, to trade the MX for the Soviet SS-24.

He, like Scowcroft, also recognized that all multiple-warhead missiles on land should be banned, not just those that are mobile. Prohibiting multiple-warhead mobile missiles would be just a first step toward eliminating all the multiple-warhead weapons.

To the Administration, this proposal had the advantage of not only reducing nuclear arms but also making the nuclear balance more stable.

Its weakness was that the Soviets would probably not agree to trade their operational mobile system for a U.S. system that was only on paper, let alone limit all multiple-warhead missiles, which formed most of their nuclear force.

The Air Force quickly accepted the idea, hoping that forgoing the MX program would improve its chances of getting money for the B-2 Stealth bomber. The Joint Chiefs of Staff went along with the Air Force.

But Cheney agreed to go along with the two-part proposal if one part of it was stiffened considerably: banning mobile multiple-warhead missiles in the START treaty and then eliminating, not just limiting, the stationary multiple-warhead missiles in a subsequent pact.

Cynics said he went along only because he believed that the Soviets were certain to reject at least the second phase, because more than half of their warheads are on land-based MIRVed missiles. In contrast, the United States has most of its MIRVed missiles on submarines.

Regardless of Cheney’s motive, that was the result. Gorbachev said the proposal was “too one-sided.”

Was the U.S. exercise all for nothing? Supporters say it at least pleased Nunn. But some experts say it unsettled the Soviets, who may have decided to show their displeasure by backtracking on other START issues.