Recently there have been indications from Soviet officials that they are willing to consider on-site inspection as a means of verification for nuclear arms control agreements. While these statements have come as a surprise to some American officials, they are in fact part of an evolutionary trend which began six years ago.
After nearly two decades of effectively rejecting on-site inspection, the Soviet position began to change in the mid-'70s. The Treaty on Underground Nuclear Explosions for Peaceful Purposes, signed in 1976 but never ratified by the United States, includes detailed inspection procedures. In a memorandum submitted that fall to the United Nations Secretary-General, Foreign Minister Gromyko indicated the Soviet Union was willing to consider ''voluntary'' on-site inspections in connection with any future comprehensive test ban.
The Soviet position continued to evolve during the comprehensive test ban negotiations under the Carter administration. The Russian ''voluntary'' proposal envisaged that a request would be made for an inspection. A refusal could be construed as an admission of guilt and as justification for withdrawing from the agreement.
However, the Soviets did not want to work out the details of an inspection - for example how many persons and what types of equipment would be allowed - in advance, but only on an ad hoc basis. In contrast, the United States wanted prior agreement on such details. By the beginning of 1978, just after two negotiating rounds, the Soviets agreed to reconsider their approach. By the end of the summer of 1978, important progress had been made in deciding which specifics could be included in a protocol. The on-site inspection discussions then bogged down, as did the talks themselves, for other reasons.
Of course, inspecting nuclear test sites is one thing; inspecting actual weapon installations would be another. At the moment, it is not clear whether inspections will be a central element in the Reagan arms control package although they may well be called for as a last resort. Warhead and launcher limits can generally be verified using ''national technical means'' such as satellites.
Other more restrictive provisions might require ''cooperative'' measures. For example, a ban on mobile missiles might require monitoring devices on each country's soil to make sure that these weapons are not roaming the countryside. On-site inspections, such as those visualized under the test ban negotiations, could sometimes clear up ambiguities which neither national technical means nor cooperative measures can deal with.
While the US has spent a great deal of time arguing over whether the Soviets would accept on-site inspections as well as other verification measures beyond national technical means, we need to ask whether the US itself is willing to accept such measures, given that the Soviets will demand equal rights and are likely to exercise them. The very individuals most concerned about Soviet cheating and therefore most likely to demand on-site inspections are also likely to squirm at the thought of Russian inspection teams operating in this country.
A case in point occurred during the comprehensive test ban negotiations. Inter-agency agreement changing the traditional requirement for mandatory on-site inspections, inspections which could not be refused, was reached only after the Joint Chiefs of Staff realized there were places in the US where they did not want Soviet inspectors poking around. A similar problem could arise in the not too distant future if the administration goes ahead with ''dense pack'' basing for the MX missile. Does the Pentagon, or anyone else for that matter, want Soviet inspectors going into the tunnels to make sure there are no extra missiles?
The problem of ''adequate'' verification of arms control agreements is not likely to fade away. Technological developments emphasizing mobility and concealment for nuclear weapons to maximize survivability will make monitoring treaty compliance more difficult. The political pressures for adequate verification are not likely to decrease. In spite of the public's desire to achieve real arms control, support rapidly evaporates if it is perceived that the Soviets could violate a treaty with impunity.
Moreover, if nuclear arsenals are really reduced, confidence in verification will have to increase since violations will acquire greater significance. It is one thing to secretly build 100 extra missiles if each side has 2000 missiles and another if each side only has 200.
As a result, on-site inspections probably cannot be avoided. It is important, however, to maintain a healthy skepticism as to their real benefits. Inspections are a deterrent to cheating and are useful for political symbolism. They might well not uncover violations by a determined evader. According to an old government proverb, ''if you need it, you can't get it and, if you get it, you don't need it.'' Moreover, since inspection is going to be a two-way street, it could entail some real costs. The US tends to assume the Soviet Union does not like inspections because it is a closed society. However, when confronted with the real possibility of Soviet inspections here, many Americans also are not likely to view the prospect with much pleasure.
For all these reasons, both the US and the Soviet Union will have a common interest in approaching inspections in a cooperative rather than an adversarial spirit. Neither country will particularly like inspections but political as well as military realities will dictate that they will have to live with them.