Vienna — Just how serious is Soviet-bloc superiority in conventional arms in Central Europe? The subject is hotly disputed. But a quick answer might be:
Serious enough to require remedial action, especially as NATO is forceably weaned from nuclear dependence.
Not so serious as to invite either a Soviet invasion or political intimidation of Europe based on the present military imbalance.
Heavily dependent in outcome, should war ever break out, on uncertain mobilization scenarios.
First the ``bean count.''
Soviet-bloc military manpower committed to Europe outnumbers committed NATO military manpower by a ratio of about 1.2:1. In itself, this is not an overwhelming advantage, but it threatens NATO because of the distribution and composition of Soviet forces.
Robert Blackwill, American ambassador to the Mutual and Balanced Force Reductions (MBFR) talks here, notes two problems: the present ``enormous forward deployment'' of 30 Soviet divisions in East Europe and the quick reinforcement potential of the 60 divisions waiting in the western Soviet Union. In the crucial central regions covered by the MBFR talks - two Germanies plus Czechoslovakia, Poland, and the Low Countries - forward deployment causes particular concern, since the Soviet bloc stationed some 230,000 more soldiers there than has NATO (on a base of just over a million each), according to Western figures.
This threat by Soviet divisions poised close to Western Europe is further aggravated by Soviet armament and doctrine. Even equal numbers of Soviet troops would have more immediate fighting power than Western equivalents, since the Soviets stress raw combat capability over logistics, while the West sacrifices today's fighting ``tooth'' to build up the logistics ``tail'' that would be needed for any extended war.
In heavy weapons, the Soviet advantage is even greater than in manpower. In main battle tanks, the Soviet bloc has a 2.6:1 superiority. In antitank guns, the Soviet-bloc advantage is 4.6:1; in artillery and multiple rocket launchers it is 3.2:1.
In combat aircraft, NATO is outnumbered 1.9:1 overall, or 1.2:1 in planes immediately available to fight in the central region.
Further Western concern arises from the Soviet Union's explicitly offensive doctrine. Soviet forces are trained to use their superior firepower not for defensive holding of territory - as NATO forces are - but for aggressive, fast offensives.
Nonetheless, even these numerical Soviet advantages in manpower and heavy weapons are somewhat reassuring to a purely defensive NATO for three reasons: the natural dominance of defense over offense in nonnuclear engagement; the West's qualitative superiority; and the combination of Soviet offensive doctrine and caution in evaluating risks.
On the first point, although the attacker has surprise and choice of terrain on his side, the defender has fortified positions and intimate knowledge of the terrain on his side. The defender normally needs fewer forces than the attacker. In the prenuclear age, the rule of thumb was that a 3:1 advantage was required to assure victory to the attacker. With today's volatile technology, nobody knows what the appropriate ratio is, but the Soviets incline to a cautious estimate. Military writer A.A. Sidorenko asserts that the lessons of World War II still apply in showing a ``decisive superiority'' for an offensive to be ``3 to 5 times for infantry, 6 to 8 times for artillery, 3 to 4 times for tanks and self-propelled artillery, and 5 to 10 times for aircraft.''
Even on the central front, the Soviets can't mass this kind of local superiority anywhere without weakening their own lines and leaving them vulnerable to NATO counterattack, argues University of Chicago political scientist John Mearsheimer in his 1983 book, ``Conventional Deterrents.''
On the second, qualitative, point, every NATO commander believes that Western forces are better man for man, gun for gun, and plane for plane. Get a roomful of American specialists together, and you're unlikely to hear anything very complimentary about the East European divisions that figure in the Soviet-bloc tally.
In addition, within the Soviet Army itself, those Central Asians who will constitute one-third of recruits are less well-educated than Slavs and are therefore less skilled at handling today's complex mechanized and electronic equipment.
In aircraft - and this balance is critical, since half of NATO's firepower is airborne - the Western qualitative advantage is especially telling. Western electronics and sensors are superior to the East's and are getting even better. Western aircraft have a longer combat radius and are better armed (with seven times the Warsaw Pact tonnage of bombs deliverable 200 miles away, for example). And Western pilots are much better trained.
NATO commanders warn against complacency based on quality alone, pointing out that raw numbers are very important. And, they say, the Soviet Union was rapidly closing the qualitative gap in weaponry in the 1970s and early 1980s. Today, speed of technological innovation is probably again widening the West-East gap.
The actual battlefield balance would depend heavily on how war broke out and who mobilized when. A decade ago, NATO planners spent a lot of time worrying that a ``standing start'' surprise attack by unreinforced Soviet-bloc troops could break through NATO lines on the North German plain. They would be at the Rhine River within a few days. Now there is less concern about this scenario than about any two-week crisis preceding an attack in which the Soviet Union might mobilize while the West, out of political caution, took only half-hearted measures to increase readiness.
The value of mobilization arises from NATO's lack of any space it could trade for time - and from the reluctance of democracies to live on a war footing. West Germany is only 150 miles east-west, and France's withdrawal from the alliance military command in 1967 deprived NATO of backup maneuver room. Either the NATO line holds at the front, or it doesn't hold at all.
West Germany has resisted erecting the kind of passive barriers on the North German plain that could slow down an invader because it hasn't wanted to imitate the infamous Berlin Wall.
This means NATO's front line is extremely weak in the first few days before troops have moved to forward positions. Yet in any crisis in which military prudence might demand early mobilization, NATO's dozen-plus nations are going to be hard put to agree on any move that might heighten confrontation.
Besides, the Soviet-bloc mobile air defense has so improved that ground troops can no longer count on the NATO air supremacy and close ground support that a decade ago was taken for granted.
Analysts such as Mr. Mearsheimer contend that the hazards have been exaggerated. If NATO moves within a week of Warsaw Pact mobilization (and if NATO's planes aren't caught as easy targets on the tarmac), the Soviets cannot build up the local force superiority needed to drive swiftly through NATO's front line.
In this context - and this is the third reason that NATO can draw some comfort from the present balance - the Soviet military doctrine of a swift offensive advance militates against any decision to attack. Christopher Donnelly, a Soviet military analyst, argues in a 1983 study of the European conventional balance by the American Academy of Arts and Sciences, that the Soviets think that superior Western military technology and the geostrategic position of Britain and the US could ``make [Soviet] victory in the central region inconclusive.'' And Soviet doctrine eschews initial advances that could be inconclusive and that might favor the West's superior logistics (and possibly encourage revolt in Eastern Europe). In the Soviet view, any invasion would have to cause ``collapse of the NATO political structure within a matter of days,'' Mr. Donnelly writes. ``If a war is to be won at all, it must be started suddenly and won quickly.''
All this is well and good for now, while the American nuclear guarantee remains, and the threat of NATO use of battlefield nuclear weapons inhibits the Soviets from massing forces sufficient to puncture NATO's thin front line. But what of the nonnuclear future that is now on the horizon? Will the current conventional imbalance then prove stable enough to maintain on its own the deterrent - prevention of war in Europe - that has prevailed during the past four decades? And if not, what must the West do to rectify the situation?
These are the questions that now obsess NATO.
Second of a three-part series. Next: The options.