Forty-five years ago, John F. Kennedy told graduating seniors at American University that peace was the "necessary rational end of rational man."
Having recently returned from a visit to the Middle East, where I met with Israeli and Arab leaders, I believe that Israel and its rivals, excluding Iran, are ready to take a rational step toward peace. But it won't happen unless the United States steps in and acts as a catalyst. Only the United States possesses the authority and the trust -- muted though it may be -- to bring the contending sides together and reach a comprehensive agreement based on a two-state formula.
The precedents are there. In the Yom Kippur War, it was the United States that negotiated the armistice and brought about disengagement. The historic Camp David Accords, pledging Israel's return of the Sinai, would not have happened without the leadership of President Jimmy Carter.
President Bill Clinton came within a hair's breadth of forging a comprehensive settlement between Israel and the Palestinian Authority. I have long urged a renewed U.S. role in stimulating dialogue between Israel and Syria, as well as Israel and the Palestinian Authority.
For the past eight years, the United States has played a subdued role, emerging occasionally to encourage the sides to talk.
President Barack Obama's appointment of special envoys to the Middle East, Pakistan and Afghanistan signals a dramatic shift from the detachment of the Bush years. Secretary of State Hillary Clinton confirmed this new approach when she declared in her confirmation hearings: "Despite the seemingly intractable problems in the Middle East, we cannot give up on peace." I personally welcome this return to an activist U.S. role. The world should, too.
The Obama administration takes office at a time when the current conflict may move each side closer to compromise if it doesn't drive them further apart. For Israel, that means cessation of hostilities, withdrawal and steps toward a Palestinian state. For Hamas, it means an end to the rocket attacks and acceptance of Israel's right to exist.
Can it happen finally? During my meeting with President Bashar Assad of Syria in Damascus, there was a clearly articulated readiness to resume stalled negotiations under Turkish sponsorship once the Israeli-Hamas conflict ends. President Assad was engaged and welcoming of the prospect. There was even a moment of levity when the president, in response to an Israeli suggestion, said that Israeli Prime Minister Ehud Olmert would be welcome at the Damascus Four Seasons once the pre-1967 lines are established, a reference to the Golan Heights.
The battle with Hamas has interrupted, but not derailed, the peace process. It is significant that not one of Israel's adversaries, with the exception of Iran, sided with Hamas' rocket attacks. Egypt backed the Israeli action, noting the aggressive stance taken by Hamas. Palestinian Authority Prime Minister Salam Fayyad conceded that Israel had acted in self-defense.
And while there has been widespread anger over the scope of Israel's response, reflecting the mood on the Arab street, there has also been recognition of Israel's right to defend itself. President Assad expressly said that he recognized Israel's security interests.
In his American University speech, President Kennedy said that "peace does not require that each love his neighbor; it requires only that they live together in mutual tolerance." This is a pragmatic formula that should suit rational men in pursuit of rational self- interests.
Arlen Specter is a Republican senator from Pennsylvania.