They are not visible in the streets of Damascus. In the covered markets, where the Czech or German accents of East-bloc diplomats can be overheard among the rug and copper merchants, Russian is rarely heard.
Soviet diplomats and advisers keep to themselves in the Tijara (commerce) district of the Syrian capital, in their embassy compound, or in nearby apartments.
But as the United States attempts to negotiate a settlement in Lebanon, which depends to a large extent on Syrian agreement, increasing attention is being paid to the growing Russian presence in Syria.
The Israelis are stressing Syria's Soviet-backed military buildup as a contrast to their own reliability as a US ally. Some US officials, notably Defense Secretary Caspar Weinberger, have labeled Syria just ''another outpost of the Soviet empire.'' The Syrians themselves are emphasizing daily that they, too, have a great power ally to back them against any potential Israeli attack.
But in reality, while Syrian military dependence on the Soviet Union has grown and while Soviet military aid has never been so important to Syrian policy , the Syrian-Soviet relationship appears based far more on realpolitik, self-interest, and disappointment in US policy than on ideology. Western analysts here believe this is a recipe for a ''client'' whom the patron would find hard to control.
The Syrian-Soviet relationship dates back to 1955 but only in late 1980 did they pursue a formal ''treaty of friendship,'' a delay which some Western analysts attribute to Syrian resistance to Soviet control. Soviet personnel have never been very popular with Syrian citizens - they mix very seldom - nor does the personnel relationship seem to have warmed today.
''The Syrians are fascinated by Western technology as symbols of progress,'' said one Damascus-based European businessman, ''and professors and students who train at East-bloc universities are considered inferior to those who study in the West.''
But the turning point in the formal Syrian-Soviet relationship came after last year's war when Soviet supplied ground-to-air missiles, planes, and tanks were decimated in Israeli battles with the Syrians in Lebanon's Bekaa Valley.
Some US officials believed the victory would increase US influence in the region at the expense of the Soviets. Instead it increased the standing of both superpowers - with moderate Arabs looking to the US to provide a regional peace solution while the battered Syrians were pushed toward the Soviets for more assistance.
The Soviets complained that their equipment had been used improperly by the Syrians. The Syrians argued they had been given less than the best.
The upshot: An outpouring of Soviet arms and advisers into Syria - up from 2, 500 before the war to between 4,000-5,000 today - in a Soviet effort to restore prestige in the Arab world and provide a more active challenge to US attempts to widen its Mideast role. Not only was lost hardware replaced but it was upgraded and expanded. Most important, the Soviets introduced two batteries of long-range ground-to-air SAM-5 missiles, each manned completely by about 900 Soviet experts , as part of a tighter and more sophisticated Syrian air defense system.
However, the door was initially left open to the United States. Syrian Foreign Minister Abdul Halim Khaddam twice visited the US after the Lebanon war, meeting two times with President Reagan. But as the US-sponsored negotiations over withdrawal of Israeli and all foreign forces from Lebanon dragged on, observers here say Syrian President Assad decided the US could not be relied upon to exert pressure on Israel. As a result he focused totally on building up his relationship with the Soviet Union.
Syrian Information Minister Ahmad Iskander Ahmad confirmed to this correspondent that Syrian President Assad made ''more than one'' (reportedly two) secret trips to Moscow last year and Soviet delegations arrive frequently in Damascus. Yet Syrian officials become irate at suggestions that Syria is becoming a Soviet satellite.
Western observers here believe the Syrians are making some trade concessions to East-bloc countries, dropping Western contracts, presumably under urging from the Soviets. Informed analysts in Damascus believe, however, that the Soviets hold no veto power over issues of vital significance to Syria.
''The Soviets get marginal concessions from the Syrians, not central ones,'' said one analyst. ''Generally the Syrians will act on what they see as their own strategic interests, and on the question of withdrawing troops from Lebanon, President Assad will not make his decision on the basis of Soviet desires.''
This realpolitik, however, may well coincide with Soviet interests, since Syria will hew to a tough line on total Israeli withdrawal from Lebanon which will be difficult for the US to accept or achieve. Moreover, on the issue of a regional peace plan, say observers, Syria would never move toward a US initiative ''without considering (its) arms supplier.'' Syria favors a peace conference under United Nations auspices with Soviet participation to achieve ''strategic balance'' in the region, rather than a Pax Americana.
The real impact of the Soviet-Syrian alliance probably lies in the increased danger of East-West conflict should an Arab-Israeli war break out. The extent of the Soviet commitment to Syria is not clear. While the Syrians talk of a ''strategic agreement,'' the treaty itself only specifies consultations in time of war.
However, Western observers believe the Soviets have probably given some form of guarantee about attacks inside Syria's borders. But even in a war limited to Lebanon's Bekaa Valley, the presence of Soviet advisers manning missile sites, who are likely to be early casualties in any fighting, guarantees at least strong Soviet political intervention. Moreover, it also boosts Syrian self-confidence.
And finally, the Syrian stress on the need to ''balance'' reliance on the US - viewed as totally pro-Israel - with links to the Soviet Union provides a concept which may be taken up by more moderate Arabs who believe that US policy is ignoring their interests in the region.