WARM WORDS ARE flowing from Washington to Damascus to thank the Syrians for their part in the freeing of Jeremy Levin, the American journalist held captive nearly a year in Lebanon by the terrorist group Islamic Jihad. Officials have it in mind that four other American citizens are still hostages and that the Syrians may yet be helpful in securing their release. The government of Hafez Assad has used the occasion to present itself to the United States in the winning role of humanitarian and enemy of terrorism.

All right: the United States needs the help of many other governments in protecting its citizens on foreign soil. But let's not get carried away by the fantasy of Syrian-American brotherhood in the cause of anti-terrorism. At some point, it would be interesting to know how it was that Islamic Jihad long managed to hold Mr. Levin -- and manages still perhaps to hold the four other Americans -- behind Syrian lines in a part of Lebanon that Syrian troops have occupied almost 10 years. Not so many months ago the United States was openly accusing Syria of responsibility in terrorist acts directed against American forces in Lebanon. This is not even to mention the ruthless violence the Syrian government has used against its own citizens at home.

The Jordanians and some PLO elements seem to be moving now toward a new round of Arab-Israeli negotiations. Whether they arrive depends, in one indelicate but essential particular, on whether the principals avoid being killed by the Syrian government or its Palestinian clients. The Syrians, distrusting the current odds, refuse to sit down with the Israelis and negotiate. They fear, however, that a Jordanian-Palestinian combination will sit down, leaving Damascus out in the cold. Assassination is a standard Syrian-favored tactic to help keep that from happening.

How, then, should the United States deal with Syria? The country has an undeniable importance in its region, as it demonstrated anew by killing the Lebanese-Israeli withdrawal accord of 1983. It has the Soviet backing to make it a significant military power and the means to stay engaged in the political maneuvers of the Arab world. American diplomats now indicate -- wisely -- a readiness to take Syria into direct account. At the least, its interest in spoiling the initiatives of others must be blunted. This appears to be one basis of Washington's rather exuberant praise of Syria in Levin's release. It will help to keep in mind, however, that the Syrians play a hard game.