WASHINGTON — American Jews may be walking into a buzzsaw as U.S. policy in the Middle East takes a dramatic turn in the wake of last week's Wye River summit.

The same shift is almost certain to ignite intense debate in Congress — with Jewish groups choosing sides. Within days of the signing, congressional Republicans, with backing from right-of-center Jewish groups, announced they would investigate the referee role proposed for the Central Intelligence Agency as part of the Wye agreement.

The real crunch will come when Washington begins judging Palestinian compliance, an intelligence issue tinged with political and diplomatic implications.

"The new American role is not an easy one, and it won't be easy for us," said Phil Baum, executive director of the American Jewish Congress. "You want [the administration] in there, being active, but you don't want them dictating terms or applying pressure. But where does one end and the other begin? That's where we run into trouble, and I'm not sure we're altogether up to that challenge."

Implementation of the Wye agreement will be contentious, with both sides seeking to influence Washington, said Mark Rosenblum, political director of Americans for Peace Now.

"It's far from clear that the president will be able to withstand pressures that will emerge when the first disputes take place over compliance, and he has to make a call on who's to blame for what," he said.

American Jewish groups, pressed by the Israeli government to provide a counterforce to administration pressure, will be right in the middle of that crossfire, he said.

Last week's agreement represented a triumph of sheer determination on the part of President Clinton and his negotiating team. But it represented something else, as well: the latest stage in the "Americanization" of the peace process.

U.S. officials will now be the arbiters of Palestinian compliance. Although the CIA's role has not been spelled out in detail, observers expect that it will actively referee in disputes over suspected Palestinian terrorists and monitor arrests and prosecutions by Palestinian authorities.

Peace process supporters say that new role, though risky, was inevitable because of the enormous mistrust that has developed over the past two years.

"Given where the peace process was before the Wye agreement, this was the best possible development," said Stephen P. Cohen, vice chairman of the Center for Middle East Peace and Economic Cooperation, a pro-peace process group.

The CIA, he said, has the experience and the expertise to provide independent, balanced information about compliance.

CIA monitoring, he added, means that "for the first time, we will have a situation in which Israel is no longer the ultimate arbiter of Palestinian life. That is the first step toward the end of occupation. That's good for Israel and for the peace process."

Some peace process supporters say the enhanced American role will lead to better compliance by both sides.

Marshall Breger, a consultant for the Israel Policy Forum and a professor of law at the Catholic University of America, said the looming American presence in the talks is a necessary evil. Washington's role, he said, "will be to take the temperature in terms of compliance and report the facts. The fact they are doing that will add to the likelihood both sides will comply."

That, he said, will "cause problems only for people who do not support the peace process, because we can assume that American civil servants, be they CIA or others, will tell the truth. So I think the peace process will be served."

But others argue that political and diplomatic considerations, not evidence, will govern the intelligence agency's rulings.

Whatever assessments U.S. officials make about compliance, "the other side will be unhappy," said Shoshana Bryen, special projects director for the Jewish Institute for National Security Affairs, a group that has been critical of the Oslo agreements. "And that will lead to political and diplomatic pressure to intervene."

Investigating Palestinian compliance will inevitably be a subjective process, she said.

"Since its impossible for anybody to completely control terrorism, the CIA will find itself in the position of judging effort. And then the game is over; when you judge effort, it becomes a political judgment. That's something the CIA is not competent to do."

Jewish groups on both sides of the peace process, she said, will inevitably be urged to affect those judgments.

Other critics put it in harsher terms — an assessment that hinted of bloody internecine battles ahead in the Jewish world.

"The CIA reports of Arafat's compliance will likely reflect the political needs of Bill Clinton, not the realities of Arafat's compliance, just as in the past five years, the State Department reports on compliance overlooked the truth and reflected political needs," said Morton Klein, president of the Zionist Organization of America, a group that has been highly critical of U.S. policy toward the Palestinians.

The ZOA, he said, plans to work with Sen. Richard Shelby (R-Ala.), chair of the Select Committee on Intelligence. This week, Shelby said he was "troubled" by the expanded role and promised congressional hearings. Peace process critics are expected to press for strong congressional opposition, particularly to the expanded CIA involvement.

A Jewish Capitol Hill staffer said that the active presence of the CIA as a monitor and adjudicator "hands the Jewish right wing the best weapon they have for throwing a monkey wrench into this entire agreement."

Other Jewish leaders, while generally supporting the Wye Memorandum, expressed similar concerns about what that expanded U.S. role would mean when the going in the negotiations gets tough.

"The problem is that the U.S., as a third-party arbitrator, will be caught in the crossfire every time there's a disagreement," said Abraham Foxman, national director of the Anti-Defamation League. The ADL is proposing a 12-week limit to the expanded CIA role — coinciding with the 12-week implementation period for the next Israeli redeployment.

"It will raise the level of disagreement between the United States and Israel," he said, "and that will attract the involvement of Jewish groups. It's a troubling development."

Foxman worries about growing polarization among American Jews as the American role expands — and as Israeli and Palestinian negotiators start battling over the most explosive issues of all, including the future of Jerusalem and the creation of a Palestinian state.

"When that happens, the Jewish community will have an even greater role in terms of advocating, explaining and supporting," Foxman said. "Just take the issue of Jerusalem; the level of contention on just that issue will be tremendous."

The growing use of the CIA to judge Palestinian compliance will inevitably increase the administration's willingness to criticize Israeli actions, as well, said Seymour Reich, a former chair of the Conference of Presidents of Major American Jewish Organizations. "That's a bullet the Israelis will have to bite. The door has been opened, and there's no going back."

Inevitably, the Israeli government — fighting for advantage in the difficult talks — will seek to use the emotional reaction of American Jews to create a counterforce in Washington to what they will regard as excessive American pressure.

"The Israelis invited greater American participation. But when these issues are tackled seriously, any genuine American role will sometimes generate pressure on both sides," said an official with a major Jewish group here. "Netanyahu has already demonstrated very clearly that he is willing to mobilize the American Jewish community to resist any degree of pressure."

The latest example came in the midst of last week's Wye Plantation talks, when Israel officials were threatening a walkout — and Prime Minister Netanyahu arranged a conference call with American Jewish leaders to explain the Israeli position.

"Ostensibly, the reason for the call was to inform," said this source. "But the underlying message was this: your government is treating us unfairly. Do something."

The temptation for Netanyahu to resort to that kind of tactic in the future will only increase, many observers say, as controversies arise over the implementation of Wye — and as the contentious final-status process begins.