World: PREPARING FOR THE UNPREDICTABLE

NO enemy is ever entirely reliable. But since the Cuban missile crisis, the U.S. and its Allies in the North Atlantic Treaty Organization have largely operated on the assumption that, in any major clash of wills, the Soviet Union would behave rationally rather than rashly. That comfortable outlook has been severely jarred by the Soviet occupation of Czechoslovakia, as the NATO Council conceded in Brussels last week. NATO's guiding precept from now on, concluded the Council in a position paper, must be the unpredictability of Soviet behavior.

"We really don't know what the Soviet leaders have in mind," observed U.S. Ambassador to NATO Harlan Cleveland. He referred to the fact that the Warsaw Pact forces moved into Czechoslovakia without having prepared a quisling regime or accurately gauged the Czechoslovaks' solidarity. Added Cleveland: "If the Russians couldn't read their close neighbors, the Czechoslovaks, any better than they did in August, how well are they reading us in October?"

Forward Positioning. The NATO Council, which is the organization's highest policymaking group, declared that, apart from the unpredictability factor, NATO must take immediate action to cope with two new threats in Europe. One is the buildup of Soviet naval power in the Mediterranean that, according to NATO, last week reached a record high of 50 ships. The other is the forward positioning of Red Army troops in Central Europe.

The Soviets seemed to be settling into Czechoslovakia for a long stay. With a treaty signed in Prague, the Russians last week imposed a legal veneer on their occupation. They reserved the privilege to intervene in Czechoslovak affairs whenever they again detect another threat of "counter-revolution." The Kremlin is likely to use that clause to intimidate First Party Secretary Alexander Dubcek from attempting to reinstate his earlier liberalization policies. On the military front, Moscow gained the right to station troops on Czechoslovak soil indefinitely.

In return for the Prague leaders' agreement on the treaty, the Soviets promised to send home all non-Soviet divisions in Czechoslovakia and reduce the number of their own divisions within the next months. According to speculation in Prague, seven divisions, armored and motorized, will remain behind. They are equipped with Scud and Frog tactical missiles that can fire either conventional or nuclear warheads. The Soviet command is setting up headquarters at Milovice, 25 miles northeast of Prague, where Russian technicians have already installed a troposcatter communications system that gives Soviet Commander Ivan Pavlovsky instant and unjammable contact with other Warsaw Pact headquarters.

Dangerous Imbalance. Under the treaty, the Soviets agreed to pay part of the upkeep costs of their troops, but the Czechoslovaks are obligated to furnish the garrisons with barracks. The Soviet air force is taking over five fields, from which it will fly MIG-21 interceptors and SU-7 and YAK-28 Firebar fighter-bombers. All in all, the Soviets will leave behind a force sufficient to keep the Czechoslovaks in line and NATO worried about the threat to West Germany's exposed southern flank.