`Minor' Issues Delay US-Soviet Arms Pact

THE Strategic Arms Reduction Treaty (START) is a grand nuclear bargain that the United States and the Soviet Union have been struggling to complete for almost a decade. Negotiators have long agreed upon the number of warheads to be cut under START, plus sublimits on various kinds of long-range nuclear delivery vehicles. Other major outstanding issues were settled over a year ago.

But progress on START stalled in recent months as the superpowers squabbled over another pact that would make large reductions in conventional arms in Europe. With those differences ironed out, officials from both nations now are making a push to overcome the final, arcane START obstacles.

``The draft START treaty is about the size of a good 19th-century novel. But it took Dostoyevsky only 2-1/2 years to write `The Brothers Karamazov,' while it's taken START nine years to get this far,'' says Jack Mendelsohn, deputy director of the Arms Control Association.

Secretary of State James Baker III offered some undisclosed ``new ideas'' for START to Soviet Foreign Minister Alexander Bessmertnykh on Friday in Geneva. Soviet officials said the ideas would receive a prompt reply, but Mr. Baker indicated considerable work remains before the treaty can be wrapped up.

The new US moves were ``evidence of a commitment by President Bush to work hard'' to finish START, said Baker.

In focusing on curbing long-range, strategic nuclear arms the START talks have attempted to control the most threatening weapons the US and the USSR have in their military arsenals. While the SALT treaties negotiated in the 1970s simply channeled and controlled strategic nuclear growth, START calls for actual arsenal reduction, making it the first true long-range arms cut treaty of the nuclear age.

Under START provisions already agreed to, each side would be limited to 6,000 strategic nuclear warheads. Taking technical treaty warhead-counting rules into account, this number represents about a one-third reduction from current stockpiles.

Central sublimits include a ceiling of 1,600 on strategic nuclear delivery vehicles, such as bombers and missiles. Only 4,900 warheads could be mounted on ballistic missiles, and the Soviets would have to cut by half their number of heavy SS-18 missiles, the weapon that most concerns the Pentagon.

Treaty verification would involve 12 kinds of on-site inspection, among them short-notice visits to declared strategic weapon sites, visits to suspect sites, inspections of deployed missiles to check the number of warheads they carry, and continuous monitoring of mobile missile production facilities.

Issues still holding up the treaty ``are for the most part second-order technical problems,'' Richard Burt, former chief START negotiator, recently told a congressional panel.

These include the details of verification involving heavy bombers and air-launched cruise missiles; what sort of permanent verification facilities will be set up outside mobile missile factories; what limits should be put on the encryption of test data beamed by missiles in flight, and whether existing multiwarhead missiles can be requalified as carrying a fewer number of warheads.

This last issue, known as ``downloading,'' is perhaps the thorniest outstanding problem. It has its roots earlier in the START negotiations, when the US expressed interest in changing its Minuteman III ICBMs from a three-warhead to a one-warhead weapon. Pentagon nuclear strategists figured that such a change would make the US land-based missile force harder to target, thus contribute to stability.

The Soviets, who don't always agree with US ideas about what's stabilizing in regards to nuclear weapons, said they didn't like the proposed change. ``It was a US discussion the Soviets would never get into,'' says a US official familiar with the START talks.

Then, claims this official, the USSR took its own three-warhead SSN-18 sub-launched missile and unilaterally downloaded it. Though the SSN-18 has been tested with seven warheads, the Soviets now say it should count as having only three. If the US agrees to change treaty assumptions accordingly, as the Soviets are now asking, ``it would give them up to 400 more warheads to fool around with and increase capabilities in other systems while still staying under START limits,'' says this official.

``We're saying, wait a minute, you wouldn't let us do it, how come you think you can?'' says the official.

Some experts within the US government object to the very concept of downloading, feeling it would make it too difficult to verify treaty limits. Others favor a compromise allowing both sides a measure of downloading.