The White House is striking a confident pose in the wake of the current impasse over nuclear arms control. But there is considerable skepticism here that the President's strategy of pushing the Soviets to the wall will eventually produce an agreement.
Many experts in the arms control community believe that progress is possible only if the two sets of suspended talks - one on medium-range missiles in Europe (INF) and the other on strategic arms (START) - are merged into one and a top-level United States negotiator is assigned to conduct the umbrella talks.
Administration officials are downplaying the fact that Moscow has not set a date for a resumption of the START talks in Geneva. They say it is not extraordinary that Soviet leaders should first want to review their own positions. This does not mean, they stress, that the Soviets are abandoning their interest in arms control.
Mr. Reagan, for his part, is portrayed as deeply committed to achieving agreements, both in INF and START. ''He has fire in his belly about arms reduction,'' commented a senior administration official last week.
Despite the administration's optimistic posture, many diplomatic and academic experts are concerned not only about the stalemate in Geneva but also about the deterioration of US-Soviet relations. They say the US has not put proposals on the table that the Soviets could reasonably accept.
''I see no hope for INF,'' says Paul Warnke, US negotiator of the unratified SALT II treaty. ''If the Soviets have to reduce 65 percent of their force and we are allowed to build 75 percent of ours, there can be no deal.''
Mr. Warnke says agreements can be reached only if a president is more than lukewarm about the idea and only if there is high-level US-Soviet communication to break stalemate when it arises. Such communication does not now exist, Warnke says, and there does not appear to be real enthusiasm for arms control.
The result, he says, is that both sides will build up their forces, making fear of a preemptive strike more plausible.
State Department analysts take a more moderate position. They see the Soviets as being squeezed by President Reagan but slowly responding to the pressure. In Europe, for instance, the Soviets initially said they would not negotiate if the US merely made the decision to deploy medium-range weapons. Yet they proceeded to negotiate. Then they put forth proposals decreasing the number of SS-20s they would install if the US gave up deployments of the Pershing II missiles.
''It is true that the Soviets will not restructure their strategic forces to accommodate the US,'' says one analyst. ''But by insisting that they do, Reagan is forcing them to come up with something. The problem - and this has been so historically - is that the Russians have never made the offers. They have always waited for the US. This administration is treating the Russians the way they have treated us, and they're not used to it.''
Another factor to be considered, experts note, is domestic politics. Mr. Reagan needs to keep the support of his right wing. He has managed to contain the influence of the hard-core conservatives, but they are still important to him. Hence he has adopted a tough public stance calculated to keep the right happy while pursuing middle-of-the-road policies.
''The important calculations are the political ones right now,'' says Marshall Shulman, director of the Harriman Institute at Columbia University. ''Much will depend on how the White House people read the public reaction. If the favorable response generated after the Grenada invasion holds through next spring and summer, the campaign strategy will lean on toughness toward the Soviets.
''On INF, too, the White House will have to await European public reactions to the second deployments,'' Dr. Shulman says. Then it will have to decide whether to build on contacts between Secretary of State George Shultz and Soviet Foreign Minister Andrei Gromyko in Stockholm next month.
While US officials see merit in keeping the heat on the Soviet Union in order to achieve a more stable nuclear relationship, they acknowledge that there may be a point of diminishing returns. Mr. Reagan's toughness has gotten Moscow's attention, causing considerable consternation in the Soviet leadership. But the risk is that he may go beyond a point of Soviet tolerance and induce an adverse response.
Experts note that the Soviets now are reassessing their defense spending and could decide to devote more resources to the military. If tensions with Washington continue to rise, they warn, the USSR will not only deploy more weapons in Eastern Europe, but will also build new systems.
''The Russians are not particularly interested in negotiations at this point, '' says Dimitri K. Simes, a scholar at the Carnegie Endowment for International Peace. They have given up on negotiating with the Reagan administration, he says , and won't try again before the election.
Dr. Simes says Reagan has managed to placate the Europeans and hold the NATO alliance together but has shown little flexibility in making arms proposals that are of interest to the Soviets.