Bonn — The re-election of conservative Chancellor Helmut Kohl means a firm West German commitment to proceed with planned NATO missile deployments later this year.
This key development in turn:
* Greatly increases pressure on Moscow to compromise on Euromissile arms control.
* Probably will decrease the obverse European pressure on Washington to compromise on arms control.
* Forces the West German Social Democratic Party (SPD) to decide clearly where it stands on missile and NATO policy.
Early returns from the March 6 election indicated that Dr. Kohl's conservatives would become the largest party in the Bundestag (parliament) after gaining nearly 50 percent of the vote. Their junior coalition partner, the Liberals, seemed likely to pick up about 7 percent of the vote - safely over the 5 percent minimum for Bundestag representation.
Together, such totals would ensure a continuation of the current coalition government. The opposition Social Democrats were expected to get only a disappointing 38.2 percent of the vote.
As for the diffuse environmentalist-nuclear-pacifist protest party, the Greens, it was evident that it would clear the 5 percent minimum hurdle and enter the Bundestag for the first time.
The missile issue was a relatively minor one in the election campaign. All the pre-election opinion polls indicated the decisive issue for voters was the economy, as West Germany enters its third year of recession and rising unemployment. Nonetheless, the deployment issue provided the only sharp policy difference between the two major parties.
The conservatives endorsed without reservation the stationing of the 572 new NATO missiles as scheduled between December of this year and 1988 in the absence of any prior Soviet-American Euromissile arms-control agreement. They argued that only clear evidence that West Germany would deploy these missiles as scheduled (along with Britain and Italy) would induce the hard Soviet concessions necessary for mutually agreed arms limitations.
If the Kremlin thought it could rely on the West German Social Democrats to delay deployment indefinitely, the conservatives contended, then Moscow could with impunity prolong its present monopoly on highly accurate land-based missiles able to reach any target in Europe. The Soviet Union currently has more than 333 of these modern three-warhead SS-20s operational, out of which approximately 222 (with 666 warheads) are aimed at Europe. NATO has as yet no equivalent weapons with a range to reach the Soviet Union.
The Social Democrats, on the contrary - in a bid for anti-nuclear votes that might otherwise go to the Greens - maintained a negative but vague position on the new NATO deployments in the West German election campaign. They have been toying with the idea of calling for a ''moratorium'' on Euromissile deployments that would block NATO from matching the already operational Soviet SS-20s.
And they have been more worried about American than about Soviet stonewalling in arms control talks.
Even if they cast their ballots on the basis of their pocketbooks, then, the West German voters have also made a clear choice about NATO missiles. Now Bonn's priority will be to put maximum pressure on Moscow to compromise in the 10 months before initial NATO stationing.
This primary pressure on Moscow will not exclude simultaneous nudges to Washington to compromise. The Kohl government has (like the British and French) already given some such nudges. And the prods are likely to get more forceful as the wave of European anti-nuclear demonstrations rises from Easter on. Kohl has no more desire to preside over a polarized society than did his Social Democratic predecessor Helmut Schmidt. And the best way to minimize polarization (and a growing public fear that the Americans are trigger-happy with nuclear weapons) is by showing the Americans to be seriously working toward arms control.
The post-election situation leaves the SPD in a tricky position, especially since there are signs that the climate of the West German missile debate has altered subtly in the course of the campaign.
Back in January, when the Social Democrats were insinuating that Kohl's conservatives were the ''rocket party'' (and, some of them, that Reagan's was a rocket administration), the conservatives were denying charges that they were militaristic or overly subservient to Washington.
By March, however - partly but not entirely as a result of the subordination of security to economic issues - the missile initiative passed to the conservatives. This time the charge was that the Social Democrats were putting the NATO and American alliance at risk by trying to weasel out of deployments. For the first time in the three-year public debate here, the planned NATO missiles came to be discussed more in terms of their impact on the arms-control talks than their impact on increasing the dangers of war.
Shadow Chancellor Hans-Jochen Vogel tacitly conceded as much at his eve-of-election press conference March 4. There, instead of once again lecturing Washington sternly that it must now match Soviet flexibility, Dr. Vogel just said amiably that he expects Washington to come up with a compromise Euromissile proposal in the next two weeks, and doesn't see why this shouldn't lead to an agreement. (Significantly, Dr. Kohl said much the same thing on the same day, even though there is no evidence at all that Washington has in fact made this crucial decision.)
For the SPD left wing, protesting the new NATO deployments remains a matter of conscience under virtually any circumstances; the changed atmosphere will not budge their opposition. The pragmatic Vogel, however, has assiduously kept all his options open, even while fishing for anti-nuclear votes.
All he has really said is that he would do everything in his power to make deployments ''superfluous,'' and that he - contrary to the policy of NATO and the French Socialists - would count the approximately 160 French and British (primarily sea-based) missiles against Soviet SS-20s.
It now remains to be seen whether the election loss will push Vogel and the SPD in a leftward direction (because of competition from the Greens in the Bundestag) or whether it will push the party in a pragmatic direction (because of the failure of the antimissile theme to galvanize voters).
On this issue, ex-chancellor Schmidt is still to be heard from. He was and is the most popular politician in West Germany, according to opinion polls. As long as he was in office, he could keep his party more or less behind the missile deployments by threatening to resign if it rebelled. He no longer has that whip - and he has kept conspicuously silent about missiles in the course of the campaign.
He is scheduled to give a major NATO speech this spring, however, and in it he might well play his Kissingerian-elder-statesman role to rally not only Bonn, Washington, and Moscow, but also his own SPD to pull together for the sake of Euromissile arms control.