A POTENTIAL breakthrough has occurred in the stalled debate over arms control treaty violations. The Soviets permitted a US delegation to visit one of their most secret and controversial military installations - the Krasnoyarsk radar. The Reagan administration's response in the coming months will indicate whether it has pushed the compliance issue so forcefully to strengthen the arms control process or to undermine it. Over the past six years, the US and the USSR have been trading charges over who is violating existing arms control agreements. The Reagan administration has repeatedly accused the Soviets of cheating on the 1972 Antiballistic Missile (ABM) Treaty, which bars both sides from developing defenses against incoming nuclear missiles. The activity most often cited as a Soviet violation is the radar screen near Krasnoyarsk in Siberia.
I traveled with two other members of Congress, three arms control staff members, a military electronics specialist, and a US scientist to the Krasnoyarsk installation. This unprecedented display of openness by the Soviets may mark a decision on their part to deal with the political dimensions of the Krasnoyarsk dispute. We should press the Soviets now to negotiate a resolution of this question.
For over four hours, our group toured the facility and was permitted to take over 1,000 photographs of the inside and outside of the buildings. The installation was clearly still under construction and, according to experts in our delegation, at least two years from being operational.
It appears that the Krasnoyarsk radar, as it nears completion in the next few years, may constitute a technical violation of the ABM treaty. But in the scramble to point the finger at the Soviets, the United States must not lose sight of why the compliance debate is important. The radar poses no military threat to the US. Its significance is political.
The Krasnoyarsk question - as well as Soviet concerns about potential US violations - undermines confidence that other global agreements will be rigidly observed. Meanwhile, the superpowers have two to three years to resolve the Krasnoyarsk dispute through bilateral negotiations. Both Soviet and US positions on the radar's legality appear overstated; there is room for compromise.
But those negotiations may never take place. The administration might well decide that it is more concerned with pursuing its own activities prohibited by the ABM treaty - namely, testing and development of the strategic defense initiative. In that case, it would see little reason to strengthen the ABM Treaty and resolve the Krasnoyarsk dispute. That would be a mistake of tremendous proportions.
Does the Krasnoyarsk radar constitute a violation of the ABM Treaty? According to the Reagan administration, the radar is intended for a battle-management role and therefore violates both the treaty's letter and spirit. That seems very unlikely. We saw no evidence during our tour of the facility that it will be ``hardened'' to withstand nuclear blasts, as required for a battle-management role. Also, the radar will not operate at the correct frequency for such a purpose.
The Soviets say the Krasnoyarsk screen is for space tracking and is permitted by the treaty. Yet the radar is not oriented in the best direction for that, will not operate at the correct frequency, and, if intended as a space-track radar, is unlikely to be very effective.
There is a third possibility. Krasnoyarsk may be an ``early warning'' radar. Judging from location alone, the radar seems best suited for this role. An early-warning radar watches the horizon to detect incoming ballistic missiles. On the other hand, the radar facility is not hardened to withstand nuclear blasts and does not appear to have independent power generation. Early-warning radars should have both of these characteristics. Radars for early warning are permitted by the ABM Treaty, but only along a country's periphery. Krasnoyarsk is about 465 miles from the Soviet border.
While less important than a battle-management radar in a military sense, an early-warning radar at Krasnoyarsk may constitute a technical violation of the ABM Treaty when fully deployed. That point is about two years away.
The Soviets claim that a number of US activities, such as the planned upgrades of US radars in Britain and Greenland, violate the treaty's restrictions on radars. These new radars will be similar to the large ``phased array'' radar under construction at Krasnoyarsk.
The ABM Treaty allows the US and the Soviet Union to modernize existing early-warning radars but not to build new ones. The phased-array radars proposed in Britain and now operational in Greenland are much more capable than the conventional radars they are replacing. The Soviets have argued that they are new early-warning radars simply constructed on the same site as the older ones. The US claims it is modernizing the aging radars as permitted by the ABM Treaty.
The US and USSR have offered varying proposals regarding radar compliance. The US first raised the issue of Krasnoyarsk in 1983, demanding that the Soviets dismantle the radar. In October 1985 the Soviets offered to halt construction at the Krasnoyarsk site if the US agreed to cancel its plans for Britain and Greenland. The US rejected the offer, claiming that American radars are allowed by the ABM Treaty. The Soviets repeated the proposal last fall.
Regardless of the technical resolution of these issues, the most important point is political. By permitting a US delegation to visit the Krasnoyarsk facility, the Soviets have signaled a willingness to raise the profile of this issue and, possibly, to seek its resolution through negotiation. More than ever before, they seem to understand that arms control will grind to a halt unless both sides are confident that treaty commitments are being observed.
Fact-finding missions such as ours can contribute to confidence-building, but ultimately the compliance question will be resolved only by serious negotiations between US and Soviet officials. The coming months will demonstrate two things: whether the Soviets are really willing to negotiate on this issue and whether the Reagan administration is willing to abandon rhetoric and meet them halfway.
US Rep. Jim Moody (D) is a congressman from Wisconsin.