Soviet propaganda on the arms talks due to open Tuesday in Geneva describes the main disagreements with the United States as unlikely to be resolved soon, if at all. It suggests that the restoration of a minimal degree of Soviet confidence in the Reagan administration as a negotiating partner is problematic at best.

Evidence here suggests a deeper pessimism within the ruling elite, which seems to be divided on the question of what Moscow can expect from the talks at Geneva.

The military establishment is reported to be the more pessimistic. Sources familiar with the thinking of senior military men say they have come to believe that the Americans have passed the point of no return on President Reagan's Strategic Defense Initiative (SDI).

According to this analysis, which is said to be shared by important civilian officials, the Americans are mesmerized by what they believe to be their substantial technological advantage and are inclined to forge ahead in development of new weapons systems.

This analysis holds that Reagan is using Moscow's willingness to negotiate as a lever on Congress to obtain larger military appropriations for his strategic weapons systems, including the MX missile.

It is argued here that the Reagan administration, having neutralized Congress in this fashion, will increase pressures on the Soviet Union, using "the SDI blackmail" as a means to force Moscow to divert additional resources to the military sector. The aim of this policy is seen as seeking to delay Soviet socioeconomic development.

A slightly less pessimistic view is said to be held by the Foreign Ministry and supported by the late president Konstantin Chernenko: that the administration is acting on the assumption that Moscow would not be able to match Reagan's SDI results. It shares the opinion of the military establishment that the administration is likely to use the talks to neutralize Congress and disarm U.S. and Western European critics of its military policy.

But this view also holds that the Geneva talks may take years, perhaps even a decade, of tough bargaining, with Reagan's second term in office being only a portion of it. It contends that Reagan has provided no evidence that he is willing to strike a deal but that it was premature to jump to a conclusion that the talks already are doomed.

This view could be described as holding that success at Geneva was possible but not likely in the coming few years in the absence of a dramatic shift in Reagan's positions.

The Associated Press reported from Geneva that Viktor P. Karpov, the head of the Soviet delegation, read a statement on arrival Sunday reiterating the point made in January's joint U.S.-Soviet declaration announcing the talks: that their objective is "reaching solutions aimed at preventing an arms race in space and terminating it on earth, at limiting and reducing nuclear arms, and at strengthening strategic stability."

Virtually all Soviet sources emphasize that Moscow since last October has been trying consistently to create a good environment for the talks. Washington, they insist, has done almost nothing since January to help create a constructive atmosphere for Geneva.

Yet the resumption of talks represents a slight forward motion for the Soviets that the sources say is regarded as important to overcome Moscow's diplomatic isolation since it broke off strategic and medium-range nuclear talks in late 1983.

Political analysts say it was this margin of maneuverability that had sustained the Foreign Ministry's argument in the ruling councils.

At a minimum, Geneva will provide the Soviets with a forum for bringing diplomatic and propaganda pressure to bear on Washington.

For one thing, Moscow can revive its efforts to drive wedges between Western Europe and the United States. Moscow appears to view Western Europeans as ambivalent toward Reagan's SDI.

Soviet media have stressed the potential for the United States moving from research to development of SDI and Washington's alleged lack of concern for its allies' security, presumably in an effort to divide Western European public opinion.

Sergei Losev, director general of the official Soviet news agency Tass, said in a commentary last night that the issue of space weapons is "the central problem" at the forthcoming talks. He described the Reagan program as "aggressive in its very essence" because it is "an attempt to gain decisive military superiority over the Soviet Union," something the Russians have said will not permit.

As Losev put it, SDI is conceived to "create a potential for making a first strike that would draw no retaliation." Economically, he said, it is a "new Klondike" for the U.S. military-industrial complex.

The Soviet Union, Losev said, "is leaving for Geneva prepared to achieve concrete results on the basis of the principle of equality and equal security." The American side, he added, has sought even before the talks started to "take outside the framework of the talks the central problems of preventing the militarization of outer space."

Losev said "one cannot but be alarmed" by what he called Washington's "unscrupulous strategies to vitiate the atmosphere around the talks from the very beginning." He concluded that Washington's recent actions must be assessed as efforts to prevent "constructive results."