Chancellor Helmut Kohl has returned from his whirlwind 26 hours in Washington radiating satisfaction. In his press interviews after coming back April 16, he displayed confidence that he achieved his double aim of maintaining personal rapport with President Reagan while heading off some potential American-European spats.
In particular Dr. Kohl:
* Received Reagan's blessing for a Kohl trip to Moscow this summer with a possible American-Soviet summit later.
* Reassured Reagan that the American President made the right action - despite continuing misgivings within his own administration - in moving toward a compromise on Euromissile arms-control negotiations last month.
* Apparently received assurance that the United States will subordinate acrimonious East-West trade issues at next month's economic summit in Williamsburg, Va., to promoting Western economic recovery.
Social Democratic ex-Chancellor Helmut Schmidt - who irritated the Reagan administration by seeing himself as a sometime ''interpreter'' between Washington and Moscow - could not have done better than the conservative Kohl.
In his time, Schmidt also succeeded in moving the Reagan administration toward policies desired by Western Europe. But with each victory, he reaped ever greater suspicion from the White House. By contrast, the striking thing about Kohl's performance so far is that in pursuing the same general policies - and in helping nudge Reagan toward that Euromissile compromise position last month - Kohl has managed to keep Reagan's trust and apparently even warm friendship.
Three things help account for this: missile stationing policy, conservative politics, and personality.
Schmidt and Kohl hardly differ in their positions on the deployment of new NATO Euromissiles planned to begin this December if there is no prior American-Soviet arms control agreement. Both have favored negotiating seriously - but proceeding with deployments if the negotiations do not lead to any arms control.
The difference here, however, is that Kohl's conservatives fully back his determination, while Schmidt's left wing constantly fought his determination.
And when Kohl makes Schmidt's same argument today - that politically he can implement missile deployments without polarizing his country only if the US demonstrates its seriousness about arms control - the White House seems to believe him in a way it never did Schmidt. This new lack of American suspicion that is so welcome in Bonn is explained in part by Kohl's anticommunist stance in the past. It is explained further by the sympathy of one conservative politician for the political needs of a fellow conservative.
Personality too explains much of the trust. Kohl likes Americans in general and Reagan in particular. And Kohl, like Reagan, is a generalist rather than a specialist, a perennial optimist, and a believer in all the old moral virtues.
Moreover, Kohl, unlike Schmidt, does not lecture others he considers inferior to him in intellect. Schmidt, having soured relations with President Carter by this habit, restrained himself with Reagan. But he never could express the same genuine pleasure in Reagan's company that Kohl does.
Kohl's April 14 and 15 talks in Washington - with Vice-President George Bush, Secretary of State George Shultz, Secretary of Defense Caspar Weinberger, and numerous senators as well as President Reagan - did not defuse all of the potential US-European quarrels. Western Europe and especially West Germany would like to see the West relax East-West tensions as much as possible during the missile stationing period so as not to hand Moscow any propaganda advantage in European public opinion during this period. The White House, on the contrary, inclines toward as much confrontation as possible with the Soviet Union.
This basic difference affects not only the Euromissile talks (in which the White House seems to be holding its chief negotiator, Paul Nitze, on short tether, while Bonn would like to see him authorized to initiate probes of potential compromise deals). It affects also the sluggish Madrid followup conference to the Helsinki East-West agreement on security and cooperation in Europe. Western Europe would like to have all the participants agree basically to the watered-down conclusion draft proposed by the neutral participants, while the US would rather see the conference fail than forego a condemnation of human-rights violations in the Soviet bloc.
These continuing differences pale, however, beside Kohl's major service to Europe in apparently persuading Washington not to press at the Williamsburg summit for a ban on subsidized Western exports to the Soviet bloc or for much tighter restrictions on export of nonmilitary technology to the East. Such an attempt would have guaranteed another major row pitting the US against its allies.