WASHINGTON — The Reagan Administration's decision to expel 55 Soviet diplomats was such a well-kept secret and such a startling escalation of the earlier rounds of tit-for-tat expulsions that many experts on U.S.-Soviet relations Tuesday found themselves literally at a loss for words.
"I don't know what the Administration is up to," said one astonished university professor. "This is amazing. I really don't have any other comment."
For years, Washington and Moscow have expelled each other's diplomats, often using them as symbolic pawns in the superpowers' endless chess game. But wholesale ousters on the scale of the one announced Tuesday are extremely rare.
And the reasons for the move offered by Administration officials left important questions unanswered:
--Why, allowing for the need to answer Moscow's expulsion of five U.S. diplomats, did President Reagan authorize retaliation that seems so disproportionate to the Soviet move?
--And, whatever the long-term need to reduce Soviet spying in this country, why was such drastic action taken just as the Administration was struggling to recover from the stalemated Iceland summit and to portray the Reykjavik meeting as evidence that progress can be made on arms control?
The action was so abrupt that even persons who usually take a hard line toward the Soviets were left asking why it was done and, maybe more importantly, why it was done now. Said a Pentagon official who first heard of the move from a reporter: "I wonder why this was done so soon after Reykjavik."
Other experts on U.S.-Soviet relations predicted that the action would touch off a "retaliation war" that Washington is unlikely to win.
"I don't think it buys us very much; it just makes us feel better," a former CIA official said.
The former official, who usually takes a hard line toward Moscow, said that the ultimate outcome might hurt the United States more than the Soviet Union if Moscow--as expected--retaliates by a massive expulsion of U.S. diplomats from the Soviet Union.
He explained that although both nations use their diplomatic missions as cover for espionage activities, the United States is more dependent than the Soviet Union on "diplomatic cover" because there are more ways to gather information in the relatively open U.S. society than in the closed Soviet society.
Some specialists suggested that the Administration move may have contained an element of domestic politics. Recent polls have shown that Reagan's firm stand at the summit was popular with the voters.
"Reagan knows one of the keys to the election is getting conservatives excited" so they will turn out and vote, said Norman Ornstein, a political analyst for the American Enterprise Institute. "This shows Reagan being tough on the Soviets and allows him to go out on the stump and say: 'The Russians have tried to intimidate me. Don't undercut me by voting for a Democratic Senate.' "
Nevertheless, Ornstein predicted the impact on the election will be small, in part because it will be difficult for the voters to absorb the issue in the two weeks remaining to election day.
In one stroke, the U.S. government ordered the Soviets to reduce by more than one-quarter the staffs of their embassy in Washington and their consulate in San Francisco.
State Department spokesman Charles Redman announced the ousters in his first meeting with reporters after his promotion to the post of assistant secretary of state for public affairs, in which he succeeded the recently resigned Bernard Kalb.
Redman, a 42-year-old career diplomat, cited two reasons for the action: to retaliate for Moscow's expulsion of five U.S. diplomats and to equalize the size of the staffs that the United States and the Soviet Union maintain in each other's territory.
Yet the massive U.S. response seems to go far beyond simple retaliation for Moscow's move, and the argument over the respective sizes of the U.S. and Soviet diplomatic missions has been going on for years.
Last year, Congress passed legislation sponsored by Sens. William S. Cohen (R-Me.) and Patrick J. Leahy (D-Vt.) requiring the Administration to find a way to equalize the size of the U.S. and Soviet diplomatic missions.
The State Department has been struggling ever since to develop a plan to bring about that numerical parity. The legislation did not specify whether the equality should be produced by reducing the Soviet staffs or by increasing U.S. representation. According to a well-informed congressional staffer, the lawmakers all along preferred to cut the Soviet representation but--until Tuesday--the State Department had been talking about increasing the staff of the U.S. embassy in Moscow and the consulate in Leningrad.
Jim Dykstra, a spokesman for Cohen, called the expulsions "very pleasing to us." He added: "The suggestion of equivalence in the embassy and consular staffs should not be cause for an international incident."