What are the Prospects for a Nuclear Test Ban?

Dec. 1, 1958
As the United States, Britain, and the Soviet Union began their negotiations on a nuclear test ban at Geneva last month, there were still misgivings in the Pentagon and the Atomic Energy Commission about the wisdom of completely binding the United States’ hands against further experimentation.

Developing cleaner and smaller nuclear weapons for both air and surface warfare is still rated a highly desirable preparation for any new war.

Presumable there were parallel misgivings in the Soviet government, for the Communists reportedly were some distance behind the West in producing a broad spectrum of nuclear weapons.

Despite the doubts, however, President Eisenhower and Premier Khrushchev decided to start the talks.

They could hardly have done less after last summer’s Geneva conclave of East-West scientists concluded that it is technically feasible to set up — with some limitations — “a workable and effective control system.”

Suppose, then, that the many difficulties looming in the way of a final agreement could be overcome. What kind of a world would we have

For one thing, tensions in the cold war might actually increase, instead of decrease, as hoped. To explain, one must begin by sketching briefly the positions of Washington and Moscow.

The Soviet Union insists that a flat, all-inclusive ban be imposed immediately and for all time, whether or not agreement is reached on an effective inspection system.

The Anglo-American offer is less sweeping and tied closely to effective inspection. “We will suspend,” Ambassador Henry Cabot Lodge recently told the United Nations, “for one year without controls, unless the Soviet Union continues testing during that period. And we are ready to extend our suspension indefinitely as long as each year we know that the inspection system is working and we are making reasonable progress on other aspects of disarmament.”

America and Britain began a one-year period of suspension without controls last October 31, but were prepared to resume testing if the Soviet Union did so first. When the Russians exploded two more bombs, November 1 and 3, President Eisenhower reclaimed the United States’ freedom to test, but withheld actual testing to see how Moscow intended to proceed — with many tests or only a few.

Assuming only a few further tests, Washington probably would go on negotiating for a test ban and it was calculated that inspection details could be ironed out at Geneva by October 31, 1959. It would take another year — until October 1960 — to install the inspection system. Britain and the United States would be prepared to extend their ban during this second year, provided there were no intensive testing or hitches in placing the inspectors.

After October 1960 Britain and the United States say they would want to see at least some progress in other phases of disarmament — reducing conventional capabilities, confining use of outer space to peaceful purposes, etc. — before making the test band permanent.

Officials in Washington concede, however, that it would be extremely difficult for the West to break the ban, once it were in effect so long.

Between the all-or-nothing Soviet position and the cautious Anglo-American position some compromise might be possible — perhaps in the direction of a two- or three-year unconditional ban, as Moscow once suggested.

Secretary of State Dulles, however, is not optimistic.

He attaches considerable validity to what he call “speculation” that the Geneva technical talks last summer “opened the eyes of the Soviet Union to the fact that our own knowledge was considerably greater than theirs about nuclear weapons… that they realized they were considerably behind in this matter and therefore they lost interest in the suspension, so that their primary purpose now is to extricate themselves from the suspension of testing without excessive damage to their propaganda position.”

Not all State Department officials share the Secretary’s view. Some of those who participated in last summer’s Geneva talks are convinced that the basic, long-range interests of the Soviet Union would be served by a genuine test ban. They expect an agreement after a long, hard negotiation and have Mr. Dulles’ backing to make the try.

These officials point out that a test band would help the Kremlin “stigmatize” nuclear weapons, so that the West would find it harder to use them against superior Soviet conventional forces.

A ban would also help to freeze out of the nuclear “club” West German and Red China, two countries which Moscow genuinely fears. (Whether or not France tests a few nuclear weapons makes little difference to the Soviet Union, it is reasoned, as long as France has not the resources to develop a big stockpile. France reportedly is close to the testing stage and refused to join in the Geneva test-ban talks.)

For its part the West sees three main advantages to an effective test ban. Russia would be opened to international inspection; the race would stop while the West was ahead, and there would no longer be world moral pressure against the United States and Britain for risking genetic damage to the human race by increasing he radioactive fallout hazard.

Assume, then, that some compromise test-ban proposal is finally agreed upon. What then

Signs from Moscow are that the war of nerves might actually increase and the atmosphere for further disarmament steps might really become less favorable.

Source of the tension would most likely be the loopholes in the test-ban agreement. Neither side could be sue the other was not testing secretly.

That there are bound to be loopholes scientists of East and West agree. In their technical a report last August 30, scientists from the United States, Britain, Canada, France, the Soviet Union, Poland, Czechoslovakia, and Rumania all conceded:

“It has been estimated on the basis of existing data that the number of earthquakes which would be undistinguishable on the basis of their seismic signals from deep underground nuclear explosions of about five-kiloton yield could be in continental areas from twenty to 100 year.”

From two to eight times a month, in other words, there may be underground disturbances that one side or the other would have to regard as an attempt by a potential enemy to break its test-ban agreement.

The report provides that “these unidentified events which could be suspected of being nuclear explosions would be inspected” by one of the 180-odd control teams spotted strategically around the globe. The teams would be provided with “equipment and apparatus appropriate to their tasks.”

The scientists’ report estimated the inspection teams would have to comb an area of forty to eighty square miles, because detection devices could not pinpoint the area any more closely. Whether the team could complete one exploration before another suspect disturbance occurred was not discussed in the report.

Prospects are, under these conditions, that Soviet inspectors might someday want to scour a city like San Francisco (44.6 square miles) or Baltimore (76.7 square miles) for evidences of an underground nuclear blast.

To be effective they would have to be given authority to take soundings — with drills or other excavation equipment — in suspicious areas. Persuading big-cit mayors of the necessity for tearing up key pieces of real estate, especially in areas where tremors are fairly common, might pose difficult problems in national-local relations. Resistance in the Soviet Union might be on a different basis, but no less difficult to overcome.

Reluctance to permit careful inspection, of course, would only intensify suspicions. The trail of litigation in the wake of the inspectors might be imposing.

Even if both sides are able to guarantee adequate access to suspicious areas, however, the most eminent seismologists in the United States have warned publicly that an unscrupulous power might cheat on a test ban.

Shortly before the technical talks began at Geneva last July, the Senate’s Special Committee on Disarmament, headed by Senator Hubert Humphrey, Democrat from Minnesota, polled thirty-one eminent American seismologists on the wisdom of a test suspension.

One of the key questions Senator Humphrey asked was how these seismologists would cheat “if you were given the problem of determining a set of conditions under which an underground nuclear explosion could be carried out without detection.”

Answers emphasized that no system of detection could be absolute, as the East-West conclave later agreed. There were many ingenious suggestions for evading an international inspection system.

The most popular region for conducting clandestine test would be earthquake-prone areas like eastern Siberia, in the Kamchatka Peninsula and Kuril Islands, or the central Asian area, on the slopes of the Himalayas. The United States, too, has “highly seismic areas,” like California.

Many seismologists suggested to Senator Humphrey that a clandestine blast might be triggered by an actual earthquake. The bomb’s trigger, they said, could be hooked up to a seismograph so the blast would go off at the instant an earthquake of large magnitude occurs.

The seismograph reading of a combined earthquake and nuclear blast would be difficult to distinguish from a routine earthquake, at least until precedents had been carefully analyzed.

Experts at Geneva established to their satisfaction that underground explosions of more than five kilotons could be distinguished from earthquakes, mainly by seismograph readings. Earthquakes produce compressions on one side and rarefaction on the other side. Explosions produce compressions in all directions.

Thus if seismographs at five or six points of the compass register compressions at a given instant in the same general area, the assumption would be that a man-made explosion had occurred. Whether it as nuclear or chemical would have to be checked on the spot.

However, if some seismographs recorded compressions and other rarefactions, the evidence would point to an earthquake.

But seismograph readings of this kind would be normally reliable only for explosion of five kilotons or greater. The theory is that clandestine testers could rig small explosions and extrapolates the results for application in bigger bomb, if necessary.

Concealment above ground would be as important as below ground, many seismologists advised Senator Humphrey.

Dr. William B. Heroy, Jr., Vice President of the Geotechnical Corporation of Dallas, Tex., suggested locating an underground test beneath a heavily wooded, highly seismic area, near normal mining operations where there are many man-made explosions. An abandoned mine would make a good site, he speculated.

Equipment and supplies for the shot should be brought in by helicopter, not by a truck whose road tracks would point to the site, he said, and the hole for the nuclear device should be drilled, not tunneled. A body of water nearby would be convenient for dumping waste material from the excavation, he suggested.

Shock waves from earthquakes travel at different speeds and to different distances, depending on the geological formations through which they pass. Relatively soft areas absorb the vibrations and reduce the distance at which earthquakes can detected.

Therefore, some seismologists advised that clandestine blasts might be set off in very porous, dry layers where the explosion would be muffled. The arctic was said to contain such areas.

Jamming of inspectors’ seismographs is also considered a likely method of concealing a secret test.

How, some seismologists inquired, would shaped nuclear charges show up on seismographs and other detection instruments available to inspectors

The Rev. Daniel Linehan, a Jesuit seismologist at the Weston Observatory of Boston College, suggested that “several explosions might be set off with slight delays, and the effect of one could mask another, confusing the interpreter of the gram [seismograms].”

Dr. Thomas C. Poulter, of Stanford Research Institute, believes that no positive identification could ever be obtained from seismographs alone. Inspectors would have to go to all suspicious areas and conduct tests to produce proof, he said.

On the other hand, he says, evaders would need only to have explanations for two factors: the underground explosion and any suspicious surface activities.

“It would therefore seem that, if a nuclear shot were fired in conjunction with a rather large mining or quarrying operations,” he wrote, “it might well be possible to conceal it from even the major portion of the personnel working at the mine or quarry. The necessary underground tunneling could be conducted on the excuse of exploring the extent of the deposit. The security could be disguised in many ways, such as a safety measure to personnel, etc. Subsequent mining operations could proceed within less than 100 feet of an actual shot location without detecting radioactivity.”

One of Senator Humphrey’s consultants proposed that a clandestine shot might be fired in a well, “drilled deep under the bottom of a shallow sea.” He reasoned that “even if the event was suspected from seismic evidence to be an explosion, it seems exceedingly unlikely that nuclear proof could be produced by inspection teams.”

Ice is a very poor transmitter of seismic energy. It was suggested that a clandestine tester might go to Antarctica and fire in the thick ice there. One expert said, “it is doubtful that a blast as large as ten kilotons would even be noticed.”

Large Arctic areas, of course, lie within the territories of the Soviet Union, the United States, and Canada.

Professor James T. Wilson of the University of Michigan brought up yet another disquieting aspect: “The Rainier [first United States underground] blast might have passed almost unnoticed seismically in the United States had it been fired in, say, western Nebraska, northern north Dakota, or a number of other such places. This is despite the fact that the United States has quite a large number of seismograph stations. It would undoubtedly have been recorded but would have probably entered the historical file as a minor earthquake in an odd location.”

These suggestions for cheating are reported in some detail here to make a point that is seldom made. It is not that the Soviet Union would necessarily try to cheat, although this could not be ruled out.

But a power as suspicious and sensitive as the Soviet Union would be sorely tempted to use its vast propaganda machine to charge the United States with conducting clandestine tests.

Senator Humphrey’s thirty-one scientist survey, of course, is ready-made material for Radio Moscow to charge that America is “plotting” to break the ban even before it is signed.

Proof that the Soviet Union I alert to American testing came last summer during the technicians’ talks in Geneva. Tass, the official Soviet news agency, suddenly announce that the United States had tested thirty-two nuclear tests in the Pacific between April 28 and July 26, or eighteen more than the Atomic Energy Commission had officially admitted.

Later it was reported that the United States had actually exploded only about thirty weapons — two less than the Soviet Union had charged.

There is no sure way for the bystander to judge, of course, whether the right number was fourteen, as Washington reported; thirty-two, as Tass announced; or some other figure. A Japanese government monitor backed up the AEC in reporting there were only fourteen, but this figure is now widely believed to be low.

The Tass report marked the first time that the Soviet Union had attempted to report on American nuclear tests, however. Some officials indicated the Reds came close to giving the right number. There was even some suspicion that Moscow added a few to the number it knew had been exploded, to see how the United States would react.

This kind of unreliable reporting, deliberate or not, could have exceedingly dangerous consequences once a test ban had been put into effect. With twenty to 100 chances a year to wonder whether an underground disturbance was a bomb or an earthquake, Soviet propaganda organs would have a large, new field for maneuver.

Past precedents are not encouraging. In the Korean War the Communists manufactured the big lie that American forces had used germ warfare. It would hardly be less difficult, some observers fear, for the Reds to pin a charge of clandestine testing on the United States.

Even if the American people did not believe it, the charge could be expected to have considerable effect in less sophisticated areas — enough effect to make the attempt attractive for Soviet propagandists.

At the same time there is the risk that the Soviet Union might herself try to cheat of course. In the case of the germ warfare charges in Korea, it was always a suspicion that the Reds were preparing a “cover” for themselves in case they needed it. Laboratories breeding possible germ warfare cultures were captured in Pyongyang, the North Korean capital, during the Korean War.

Some American officials have advanced the idea that the Kremlin might try another method of discrediting the United States, particularly if it wanted to resume testing once a suspension were ordered.

Suppose, they say, that the Soviet Union were to dispatch a submarine to the United States’ Eniwetok proving grounds and “plant” a nuclear explosion there. The Moscow could denounce the United States for breaking its agreement and justify resumption of its own tests.

Those who think it best to press forward with a test ban contend that all these attempts at sowing confusion could be exposed. Moreover, they believe, the basic interests of the Soviet Union would better be served by maintaining quiet.

Senator Humphrey believes that the risks of accepting a test-suspension agreement are preferable to the risks of going on with the feverish arms race.

He wrote in his report last summer that “an inspection system for a nuclear test moratorium could provide a high degree of assurance that no country would risk violating the agreement by trying to conduct tests in secret.”

Scientists of East and West calculated the “high degree” was about ninety percent. Cheaters would run a ninety percent risk of being caught, they reported. Some American officials believe a mere fifty percent risk would be enough to deter the Soviet Union or any other power.

Even if they are right, the West may find it more difficult to protect against psychological warfare in this deadly serious area, where a propaganda feint might lead to war.

Last spring the Soviet Union took a similar risk. Moscow aired charges in the United Nations that the American Strategic Air Command was sending its bombers toward the Soviet Union and risking retaliatory strikes from Russia.

This may be the prototype of the war of nerves in store for the world if a nuclear-test suspension is ever arranged.

The Administration appears to have decided an agreement will be worth it — in terms of opening the Soviet Union to inspection and confining the spread of nuclear weapons to other countries.

About the Author

Mr. Voss is diplomatic correspondent for the Washington Star. He was formerly on the editorial staff of the Sunday Star. Before joining the Star in 1951. Mr. Voss served six years in General MacArthur’s public relations office in Tokyo.