Moscow played only a perfunctory and pro forma role in the Lebanese crisis. It made low-key noises about the wickedness of Israel. It resupplied the Syrians , partially, after the Israelis shot down most of their planes and knocked out most of their tanks.
But in substance Moscow was a bystander at this affair.
It did not even try to play a strong role.
It did not demand that it be admitted to peace talks.
All of which poses an intriguing question for the Kremlin watchers of the Western world. Why did Moscow, sometimes quick to fish in troubled waters, keep out of this one?
The obvious superficial reason is that with Leonid Brezhnev supposedly nearing the end of his leadership and the prevalence of doubts about the succession, Moscow is in no condition to pursue a forward or assertive foreign policy.
There may be something to this but it must be noted that Moscow diplomacy has been active in regard to China. For months now Moscow has been courting China. This week Leonid Ilyichev, a deputy foreign minister of the Soviet Union and a prominent Communist Party figure (he was editor-in-chief of first Izvestia then Pravda during his rise to prominence) arrived in Peking obviously to try to mend relations with the Chinese. So there is no general paralysis of Soviet foreign policymaking.
The reasonable conclusion from the above is that Moscow played a bystander role over Lebanon not because of paralysis in the Kremlin, but because it served Soviet interests better.
President Reagan in his latest press conference last week remarked that ''the Soviet Union, which has been expanding over the years vastly in the territory and the people coming under its control, they haven't expanded into an extra square inch since we've been here.''
That version of current history may make effective political propaganda in an election year. But we must hope that it is only campaign propaganda because we could be in trouble if Mr. Reagan really believed that his ''hard line'' rhetoric toward Moscow has actually caused the Soviets to slow down.
The truth of the matter is that the Soviets passed the peak of their physical expansion long before Mr. Reagan reached the White House. They have been on the decline in physical power spread since Richard Nixon went to Peking. They since have been relying more on diplomacy and on the mistakes of others than on military power.
The Soviets do whatever they think is in their best interest at any given time. Right now they are gaining more influence and friends by playing a low-key game in the Middle East than they could hope to gain by muscle flexing or land grabbing.
Just pause a moment and try to think (and then shudder) about what the world would be like if Western Europe were to cut itself free from the American alliance and become friendlier to Moscow than to Washington. And then, after you have considered that chilling possibility, dwell for a moment on how much still worse things would be for the US if China also swung away from Washington and became once more friendly with Moscow.
Neither of these things is going to happen. Western Europe and China both have too much need of American wealth, technology, and strength. But both are quite capable of seeking a less committed relationship with Washington. Both would enjoy some advantage in bargaining power if they became less committed to the US and less distant from Moscow.
As of today the drift is in that direction largely because Moscow has been using soft rhetoric as the answer to Mr. Reagan's hard rhetoric. Mr. Reagan has frightened his allies. Mr. Brezhnev has been soothing them. Just not trying to get in on the Lebanon crisis may well be part of the soothing process.
It works that way even if not so intended. The Soviets kept out. But America was there in the sense of supporting Israel, which in turn supports the Phalangists, whose forces did the killing at Shatila and Sabra. The US does not sell guns to the Phalangists. It does provide military aid to Israel. Israel has been supplying the Phalangists.
The US gets some of the blame for the massacre of Palestine Arabs. The Soviets gain - by being quiet on the sideline. The mere fact that they are not on speaking terms with Israel gives them an advantage with all the Arabs. It also puts them in step on this point, among others, with the West Europeans. Moscow had nothing to gain by getting mixed up in the Lebanon affair.
Doing nothing noisy, or blustering, or military can in itself be an active foreign policy. Right now there is a widespread feeling in Europe that Reagan foreign policy points toward more tension and more danger. Many a European is more afraid of Ronald Reagan than he is of Leonid Brezhnev.
If Moscow foreign policy is played softly these days, it is not because Mr. Reagan has scared them. It is because it may pay dividends.
It might even break up NATO.