Syria may not be as indispensable to Mideast peace as its president, Bashar Assad, says it is, but when John Kerry visits Damascus this weekend as the new chairman of the Senate Foreign Relations Committee, he will have an opportunity to prepare the way for a new policy of dialogue with Syria.

Kerry has shown on earlier stops in his Mideast trip that he is receptive to Lebanese and Israeli concerns about Syria. He made it clear that a US-Syrian rapprochement will require Assad to stop meddling in Lebanese politics and to back away from support of the Lebanese Shi'ite militia Hezbollah, Palestinian Islamic Jihad, and Hamas.

This is obligatory rhetoric. Kerry could hardly tell America's friends in Lebanon or Israel that their interests will be disregarded in a renewed diplomatic dialogue between Washington and Damascus.

Still, the reality is that Israel and Lebanon both stand to gain from the right kind of US engagement with Syria. The same is true for Egypt, Jordan, Saudi Arabia, and other Arab states that support the 2002 Arab Peace Initiative with Israel and fret about Iran's influence in their region.

All these interested parties would want a US overture to Syria to advance their own aims. Among these are an Israel-Syria peace agreement leading to a two-state solution of the Israeli-Palestinian conflict; the disarming of Hezbollah in Lebanon; and - perhaps most important of all - prying Syria away from its marriage of convenience with Iran.

In a recent interview with the British paper the Guardian, Assad was emphatic in describing what he has to offer the Obama administration. "If you want comprehensive peace in the Middle East you can't achieve it without Syria," he said. "We are a player in the region. If you want to talk about peace, you cannot advance without us."

Kerry need not challenge this traditional Syrian assertion when he meets Assad. But he can tell the Syrian ruler what the Obama administration expects in return for taking an active role in bringing about a peace accord between Israel and Syria. And Kerry should sound out Assad on how far he is willing to go in reciprocating American gestures of good will, particularly on the central issue of Syria's alliance with Iran.

Assad makes no secret of his wish to reconcile with America by reaching a land-for-peace deal with Israel. He wants a return of the Golan Heights, an end to US sanctions, an inflow of Western investment and technology, and some way to derail a United Nations tribunal's indictment of senior Syrian officials for the 2005 murder of former Lebanese premier Rafik Hariri. It is not Kerry's place to promise any of these benefits, but it will be his role to advise whether Assad is somebody with whom President Obama can do business.