There's agreement among members of the U.S. Congress that American participation is a necessary ingredient for peace in the Middle East. But as violence continues to rock the region, the objective for peace may shift.

U.S. envoy Anthony Zinni is in Israel for the third time since the 18-month Palestinian uprising began, trying to broker a cease-fire to the bloodshed.

Israeli Prime Minister Ariel Sharon has condemned the bloody attacks and warned that his government will respond with violence at any time.

That makes Arizona Republican Senator John McCain wonder whether the two sides could ever live side by side in peace. "I believe we have to figure out a way for Palestinians and Israelis to live apart," he said. "That's a very difficult thing to do, but the present situation and endless bloodshed on both sides is something that could escalate out of control and could envelope the entire Middle East."

Senator McCain made his comments on the television program Fox News Sunday.

Mr McCain was asked whether a solution to the problem might be getting Israelis out of Palestinian occupied areas, and moving Palestinians from Israeli occupied zones.

"At least set up barriers between the two elements," he said. "And I know that would present some very difficult decisions, at least as the Israelis are concerned, because of [Jewish] settlements, but it would also entail a huge expenditure of funds. But I don't know how you continue the status quo without us having a major, major escalation that could envelope the entire region."

Senate Majority Leader Tom Daschle (Dem.-S.D.) agrees that the situation in Israel is bleak. But Sen. Daschle says an American presence is an essential ingredient for the Middle East peace process.

"I think our presence there is the only thing that will offer the stability that will be required if we begin the talks," he said. "So, there is no doubt that unless we're there, we really can't be optimistic about the future."

Senator Tom Daschle made his comments Sunday on the CBS television program Face the Nation.