But, will they talk?

President Reagan was confident in his turn-of-the-year interviews that there is nothing really dangerous in Soviet-American relations and that the New Year will find the Soviets back at the bargaining table.

He has a new reason for hoping his optimistic predictions will come true. Polls taken by the George Gallup organization show that the American people have begun to worry about his military policies.

A poll taken in October of 1982 showed 62 percent of Americans concerned deeply about unemployment, but only 6 percent about the ''threat of war.''

A poll taken one year later in October of 1983 showed an unusual amount of change. Concern about unemployment had dropped to 42 percent, but concern about the ''threat of war'' had gone up to 23 percent.

One month later, in November, after Grenada and the bombing of the United States Marines barracks in Lebanon, ''the threat of war and international problems'' had become the top concern of the American people at 37 percent. Unemployment concern had dropped to second place at 31 percent.

Politicians are sensitive to this kind of shift in public concerns. It explains, of course, why Democratic candidate Walter Mondale came out over the past weekend for withdrawal of the US Marines from Lebanon. It explains why Republican Sen. John Tower, who heads the Senate's military affairs committee, went to Lebanon on Monday to find out whether he agrees with Mr. Mondale. Sen. Barry Goldwater was only the first on a long list of other prominent Republicans who have already said ''get out.''

Leading conservative Republican commentators, such as William F. Buckley, William Safire, and James J. Kilpatrick, are also on record now for withdrawal.

According to President Reagan's political teachings, the one thing the Soviets understand and respect is strength. He has repeatedly asserted that, if and when the US has built up its military power and showed its willingness to use it, the Soviets would be ready and willing to do business with him.

Well, 1983 was the year in which the President showed his willingness to use US military power. He used it in Central America, on Grenada, on the Gulf of Sirte, and in Lebanon. By doing it, he first worried the NATO allies. Now he is worrying Americans at home.

All will come out well for Mr. Reagan if the Soviets behave according to his own formula. But Columbia University Soviet expert Seweryn Bialer has recently returned from a visit to Moscow, saying (Time magazine, June 2, Page 35) that ''the U.S.S.R.'s distrust of Reagan is now so high that Moscow would probably reject even the most reasonable U.S. arms control proposal.''

Mr. Bialer and other leading American experts on the Soviet Union have expected that 1984 would see the Soviets doing anything they can to embarrass and humiliate Mr. Reagan. They are already twice confirmed in their expectations. The Syrians have released a US Navy flier, Lt. Robert O. Goodman Jr., to Democrat Jesse Jackson - after refusing to release him to President Reagan's special Mideast ambassador Donald Rumsfeld. And the Syrians had earlier spoiled Mr. Reagan's plans for Lebanon by denouncing the agreement between Lebanon and Israel. This made it impossible for Lebanese President Amin Gemayel to implement the agreement. Syria then blocked progress toward reunifying Lebanon under the Gemayel regime, simply by refusing to withdraw Syrian troops from Lebanon.

Soviet resupply of Syrian arms was behind both of Syria's anti-Reagan actions. It is also behind the direct pressure being put on the US Marines by Druze and Shiite militias. If Mr. Reagan now finds it necessary to withdraw the Marines, he will have been frustrated in his Middle East purposes and embarrassed by having started something he could not finish.

It was easy for Moscow to impose the Beirut predicament on Mr. Reagan. They can impose another embarrassment by simply ignoring overtures he may make now toward talks about nuclear weapons.

The Soviets have little to lose, and perhaps much to gain, by refusing to play their assigned role in the Reagan scenario. The fact of no negotiations going on between Moscow and Washington increases the strain within the NATO alliance and political doubts about Reagan foreign policy on his own home ground. Mr. Reagan has lost, not gained, bargaining power against the Soviets by his strategy of building first and expecting to talk later.