NEWS ANALYSIS : Global Nuclear Threat Eased, Hardly Ended

President Bush’s nuclear arms proposals move the world a step back from the threat of nuclear incineration. They are, as advertised, a series of important moves unmatched in the costly and terrifying Cold War nuclear competition with the Soviet Union.

And yet, even if every one is carried out, both superpowers will continue to command nuclear arsenals capable of unthinkable destruction. The thermonuclear weapons carried aboard a single U.S. Trident ballistic missile submarine--a class of weapons untouched by the Bush proposal--could still obliterate the Soviet Union’s 50 largest cities within 30 minutes of launch.

Immediately following the unsuccessful Moscow coup in August, Bush began discussing with National Security Adviser Brent Scowcroft how the United States could capitalize on a Soviet Union so beset by internal problems that it no longer posed an immediate threat to the United States or any of its neighbors.

Bush resolved to take the chastened Soviet and Russian leaders at their word when they offered to discuss massive reductions in the superpower arsenals. And with an eye toward potential instability in the restive republics that are straining to escape Moscow’s domination, Bush sought rapid action on the weapons thought to pose the greatest risk--the thousands of short-range systems such as artillery shells and battlefield missiles that could be used as weapons of terror.

The President wanted, as a senior official said Friday, “to take advantage of a historic opportunity to dramatically reduce the number of nuclear weapons, enhance stability and reduce the risk of war.” Bush also hoped to use U.S. action to prompt the Soviets to redirect much of the huge economic effort required to develop, build and maintain their nuclear stockpile.

Upon returning to Washington following the Labor Day holiday, Bush instructed Defense Secretary Dick Cheney to come up with a plan to reduce the American nuclear arsenal in ways that the Soviet Union could quickly match. After extensive consultations with the Joint Chiefs of Staff and his civilian advisers, Cheney presented a plan to the President that would, in essence, de-nuclearize the surface fleet of the U.S. Navy.

Cheney proposed to remove all nuclear-tipped bombs and missiles carried aboard aircraft carriers, battleships and cruisers, as well as nuclear cruise missiles deployed on surface ships and submarines. They would be stored in bunkers in the United States and not placed aboard any ships except in times of crisis.

Bush rejected the initial Cheney plan, asking for a broader initiative, one that encompassed all so-called tactical nuclear weapons--the portable, concealable and widely deployed weapons that were developed chiefly to offset the overwhelming Soviet advantage in conventional weapons and manpower.

Bush, his advisers said, wanted something dramatic, something that signaled that he is not trailing the disarmament parade, but leading it.

On Sept. 16, Cheney returned to the White House with the sweeping proposals presented Friday night. Three weeks of intensive study in the Pentagon yielded the initiatives, which are at once more than anyone expected of this cautious Administration and less than its critics had hoped for.

Since the collapse of the Warsaw Pact in late 1989, nuclear strategists outside the Administration had questioned the need not only for the tactical weapons eliminated by the Bush plan, but also for the thousands of long-range weapons that would remain even after the Strategic Arms Reduction Treaty (START) is ratified and implemented.

The old question--”How much is enough?”--re-emerged in urgent voice after it became clear that the Soviet Union is in no position to launch an attack on Europe or to credibly threaten the United States with global war.

Nuclear experts, among them former Defense Secretary Robert S. McNamara, revived the concept of “minimal deterrence,” the retention of a few hundred nuclear warheads atop accurate, single-warhead missiles as sufficient to deter war. Others argued that America’s domestic problems were far more pressing than the expensive drive to continue developing new generations of increasingly deadly and accurate nuclear warheads.

These critics will not be satisfied with Bush’s proposals for several reasons: The President still wants to develop the Midgetman missile and the B-2 bomber and still intends to push the Strategic Defense Initiative conceived during the Ronald Reagan Administration.

But the initial overall reaction was positive. Jack Mendelsohn, deputy director of the Washington-based Arms Control Assn., applauded parts of the speech for offering the Soviets “sweeteners” to improve the safety and security of their nuclear weapons, many of which are decades old and lack sophisticated protective devices.

Bush’s proposal to remove tactical nuclear weapons from U.S. ships may indeed help the Soviets “do what we would like them to do and what they think themselves they ought to do”--to withdraw and destroy their own tactical nuclear weapons, Mendelsohn said.

Similarly, taking American nuclear bombers off hair-trigger alert may help coax the Soviets to put their mobile land-based missiles back into their garages, a step Soviet commanders took during last month’s coup attempt to reassure the world that the political turmoil did not threaten the peace.

But while Mendelsohn called these acts shrewd gestures toward the Soviets and wise concessions to reality, he said Bush’s call for the Soviets to cooperate in building missile defenses “doesn’t make sense.”

“It runs contrary to logic: When you’re reducing your strategic forces, you don’t build defenses against the few that remain,” Mendelsohn said. “To pursue such defenses would be to sabotage strategic force reductions.” His group advocates strict adherence to the 1972 Anti-Ballistic Missile Treaty, which forbids deployment of most anti-missile systems.

Edward L. Warner III, a Soviet affairs specialist at the RAND Corp. in Washington, said Moscow would likely embrace many of the Bush proposals although differences remain on questions of the two nations’ deadliest weapons--the multiple-warhead intercontinental missiles based on land and at sea. Those discussions will be difficult and protracted, he predicted.

On the timing of the announcement, Warner said Bush genuinely wanted to appear responsive to the changes under way in the Soviet Union. But he also noted that Bush’s defense budget is taking a pounding on Capitol Hill and that the President used the speech to plug his two most expensive weapons programs, the B-2 bomber and SDI.

“In the wake of the coup attempt, he wanted to put best possible arguments in favor of the defense budget,” Warner said. “It was a response to the criticism on the Hill for the need to further adapt American defense policy and the American defense program in light of cascading events.”

The Bush plan will be welcomed not only in Moscow and the capitals of Europe but throughout a world in which nuclear weapons aboard U.S. warships have been a source of political strain for years.

New Zealand barred Navy port visits because the Navy refused to confirm or deny the presence of nuclear arms aboard ships. Japan officially demanded that U.S. ships not sail into its harbors carrying nuclear weapons although hundreds did so without declaring their armament.

But, as a senior official pointedly noted Friday night: “We are not getting rid of all nuclear weapons. We are significantly reducing the numbers on both sides.”

A thousand nuclear-tipped missiles remain in silos across the United States, 40 ballistic missile submarines still carry 6,000 nuclear warheads and thousands of bombs and missiles are stored at Strategic Air Command bases, ready to fly on B-52 and B-1 bombers. Hundreds more nuclear bombs are in depots in Europe for potential use on shorter-range bombers such as the F-111.

But by taking all the strategic bombers off “strip alert”--armed, fueled and ready to fly at a moment’s notice--and by removing all nuclear weapons from surface ships at sea, the United States has considerably lengthened the time it would take to launch a full-blown nuclear assault. Defense officials said that rearming the bombers would take at least several hours, while bringing the fleet home to be outfitted with nuclear weapons might take as long as three weeks.

Times staff writer Melissa Healy contributed to this story.