Washington — Arms control analysts are pressing the question: Is there any point in keeping the two levels of arms talks in Geneva on separate tracks and is there any point in limiting the discussions just to the two superpowers?
For many experts and participants, the US-Soviet impasse at Geneva over intermediate-range nuclear weapons raises questions about the basic structure of arms control talks. For three years, there has been no significant progress at either the START (strategic arms reduction) or INF (intermediate-range nuclear force) negotiations.
In part, this has to do with what some experts see as this artificial separation and the important factors that are excluded but nonetheless hang over the nuclear equation. Two examples:
* Great Britain and France each have a modest nuclear capability. Most of these forces are submarine-based missiles, relatively old and less accurate, inoperable when in port.
But both countries are proceeding with the steady modernization of these forces, including the highly accurate US-made Trident II submarine missile in Britain. These improvements could increase the number of targetable warheads held by the two countries at least five-fold.
* While the Soviet Union since last spring has frozen its deployment of the new SS-20 three-warhead missile aimed at European targets, it has continued to deploy new SS-20s in Asia. The missile is mobile and presumably could be moved into Europe.
Meanwhile, the People's Republic of China continues to improve its stockpile of nuclear weapons (now numbering several hundred) and its delivery systems, including cruise missiles on submarines. It has tested ballistic missiles with multiple warheads.
Yet neither the British, French, nor Chinese nuclear forces are included in the Geneva talks. And the Soviet nuclear forces in Asia have been treated only indirectly.
Canadian Prime Minister Pierre Trudeau this week took to Peking his plan, outlined at the Commonwealth summit in India, for a worldwide nuclear arms freeze and meeting of the five known nuclear powers.
This reflects the concern by many nonnuclear countries about worsening relations between the superpowers. But the plan is not likely to be acted on soon, and the merging of START and INF talks at Geneva also seems unlikely given the current US and Soviet positions.
While some officials in Washington have expressed mild interest in the idea, the official view is that melding the two sets of talks probably would confuse things and make it even less likely that the Reagan administration could win any arms control agreement.
''It's a subject that's in the air,'' said one State Department source. ''But broadly speaking, it would simply complicate both negotiations with the problems of each. . . . They were always intended to be done in close coordination with each other and they have been.
''Our negotiating strategy in each has been closely coordinated both in Washington and in Geneva. Each negotiation has a history of its own now.''
This holding steady in response to the recent Soviet walkout at Geneva and heightened antinuclear protests in Western Europe also reinforces the notion that the administration's first priority is nuclear modernization, especially the Pershing II and cruise missiles now being set up in allied European countries.
''What we've assumed is that if we didn't deploy, there was no prayer for an agreement,'' Assistant Defense Secretary Richard Perle said Sunday on the CBS television program ''Face the Nation.''
''A steady course . . . is the only way to bring about an eventual agreement, '' he said.
But the hesitancy to change the structure of the talks also is part of the uncertainty here about the stability of Soviet leadership these days and an unwillingness to appear too disposed to change direction (not to be confused with appearing ''flexible'').
Many experts, however, feel that it makes no sense to keep the two sets of talks at Geneva separate. And even Brent Scowcroft, chairman of the President's Commission on Strategic Forces, has acknowledged that INF and START probably will have to be combined at some point.
''The distinction between intermediate-range and intercontinental weapons is an artificial one,'' maintains Gene La Rocque, a retired Navy admiral and the director of the Center for Defense Information. ''Combining negotiations will give both sides more opportunity to agree on equitable, balanced arms reductions measures.''
In a recent column in the New York Times, Massachusetts Institute of Technology president emeritus Jerome Wiesner wrote: ''The talks as organized today do not make any sense - above all because technological developments make it futile to negotiate separately about any single category of nuclear weapons.''
Earlier this fall, three former senior US arms control officials - former Arms Control and Disarmament Agency (ACDA) director and SALT II negotiator Paul Warnke, former ACDA director and SALT I negotiator Gerard Smith, and SALT I legal advisor John Rhinelander - outlined a two-phase plan for setting combined ceilings on intercontinental and intermediate-range nuclear weapons by means of a single set of negotiations.
''Because of the trade-offs that will have to be made across the spectrum of intermediate- and intercontinental-range systems in order to reach agreement, we believe it is important that the President appoint one special representative to seek breakthroughs in both the START and INF negotiations,'' the three men wrote to General Scowcroft.
At least for the moment, however, there seems little chance that such advice will be followed.