By ALAN FINDER
When John J. Mearsheimer, a 58-year-old political scientist at the University of Chicago, decided to take on the United States' support for Israel, he considered the subject too touchy to confront alone.
So he enlisted a colleague to help provoke a public discussion. Like Dr. Mearsheimer, Stephen M. Walt, a 50-year-old professor at the John F. Kennedy School of Government at Harvard, is a specialist in theories of international relations and a tenured professor with a prestigious chair.
"I think it's in the national interest to have a debate on this," Dr. Mearsheimer said. "I don't think it benefits anyone to keep this in the closet."
The resulting paper, "The Israel Lobby and U.S. Foreign Policy," was published last month in the London Review of Books, after an earlier draft was rejected by The Atlantic. Editors at The Atlantic declined to discuss why.
A longer, 42-page version of the article, with an additional 40 pages of footnotes, was also posted on the Kennedy School's Web site.
The paper asserts that the United States' support of Israel has been unwavering, has jeopardized American security and has been driven by "the unmatched power of the Israel Lobby," which the authors describe as a loose coalition of American Jews and their allies.
They say that the United States was singled out by Al Qaeda in large part because of American support for Israel's occupation of the West Bank and Gaza and that a significant motivation for the invasion of Iraq was to improve Israel's security.
The essay has caused an uproar. First came headlines in The New York Sun and The Forward, the 108-year-old Jewish weekly, followed by critiques in opinion journals like The New Republic and The Weekly Standard, along with myriad newspaper op-ed articles.
Many of the articles have castigated the paper as historically inaccurate and sloppy in its scholarship, with some critics saying for example that Osama bin Laden first focused on the United States because of its support for the Saudi government. Many have also criticized the professors as defining the so-called pro-Israel lobby so broadly as to render it all but meaningless, and as implying, by referring to it always as "the Lobby" with a capital L, that it operates in a monolithic, if not conspiratorial manner.
While condemnations have been fierce at home, the article has drawn some praise in British publications for stimulating debate.
The Kennedy School removed its logo from the cover page of the essay on its Web site to make clear that it contained the professors' opinions and analysis, not the school's. But Harvard and the University of Chicago have stood behind Dr. Mearsheimer and Dr. Walt, with officials citing the need to protect free expression.
"This is a kind of classic call in academic freedom," said David T. Ellwood, dean of the Kennedy School. "If universities stand for anything, they stand for getting ideas out there and then for open debate. Some ideas are controversial, some ideas are very controversial, some ideas are wrong. But the administration shouldn't be in the position of making a judgment on something like this. Other scholars should be making those judgments, and ideas should rise and fall in the bright light of scholarly debate."
Some Harvard colleagues of Dr. Walt have entered the debate full-throated, including David R. Gergen, also at the Kennedy School and a former adviser to four presidents, and Alan M. Dershowitz, a professor at Harvard Law School, described in the paper as an apologist for Israel.
The Kennedy School invited members of the Harvard faculty to post responses on the Web site, as long as they were scholarly and were not personal attacks. Mr. Dershowitz posted a 45-page response last week in which he attacked the authors' logic and facts. He also asked why they recycled accusations that "would be seized on by bigots to promote their anti-Semitic agendas."
The article asserts that the Israel lobby includes members of the Clinton and the Bush administrations, Jewish organizations, Christian evangelicals, thinkers referred to as "neo-conservative gentiles" and an array of policy organizations.
"There is this blanket denunciation of a very large number of American Jews and an accusation of disloyalty," Eliot A. Cohen, a professor at School of Advanced International Studies at Johns Hopkins University, said in a telephone interview.
In an opinion article in The Washington Post last week, Dr. Cohen described the paper as anti-Semitic and "a wretched piece of scholarship."
Dennis Ross, a former Middle East negotiator for the United States, said he found the paper "incredibly simple-minded." He was listed in it as an official with "close ties to Israel or to prominent pro-Israel organizations."
"If this lobby is so powerful, how come every major Arab arms sale that they opposed they lost on?" Mr. Ross asked.
Now counselor at the Washington Institute for Near East Policy, a research organization, Mr. Ross also said that Dr. Mearsheimer and Dr. Walt had misstated American positions in peace negotiations with the Israelis and Palestinians during the Clinton administration.
Dr. Mearsheimer said that the response was not unexpected, but that he had been surprised by some of the vitriol.
"We certainly wanted to provoke a debate, and this has happened," he said. "But we hoped to provoke a rational debate, not a food fight in which people accuse us of being anti-Semites."
Dr. Walt and Dr. Mearsheimer are prominent in the academic world, part of a group of foreign policy analysts, known as realists, who believe that international politics is fundamentally about the pursuit of power. Each has written extensively on foreign affairs and theories of international relations, although they are not experts on the Middle East.
Dr. Walt has written books on how other nations have responded to the global power of the United States and on international alliances. Dr. Mearsheimer, who graduated from the United States Military Academy at West Point, has written books on deterrence and great-power politics.
In the first article they wrote together, in 2003, they opposed the Iraq war.
Dr. Mearsheimer said that he and Dr. Walt had stated in their latest essay that they were not contending that American Jews and their allies were engaged in a conspiracy to put Israel's strategic needs ahead of those of the United States.
"We never used the word 'cabal,' " Dr. Mearsheimer said. "It's not in our vocabulary. And I think it would be completely irresponsible to suggest that it is a cabal or a conspiracy."
"This is a classic case of interest-group politics," he said of the pro-Israel lobbying in Washington. "It's as American as apple pie."
Dr. Walt and Dr. Mearsheimer said that most of their colleagues had treated them well, including those who disagreed with them.
"The response of colleagues has been on one level uniformly supportive of the basic principle of academic freedom," Dr. Walt said. "I have received a number of messages from colleagues, at Harvard and elsewhere, that were strongly supportive of our basic argument. I have also received some very thoughtful responses from colleagues at other universities taking issue with arguments we've made."
Both men said they had expected consequences from having published the paper.
"We both knew from the get-go that whoever wrote this piece would essentially be committing career suicide in terms of getting a high-level administrative job in academia or a policy-making position," Dr. Mearsheimer said.
(Dr. Walt's intention to step down this summer as the academic dean at the Kennedy School was announced in early February, before the essay was published.)
Some critics of the paper dismissed the idea that Dr. Mearsheimer and Dr. Walt might be punished for expressing their ideas.
"Honestly, one of the things I found distasteful is the pose of martyrdom," Dr. Cohen of Johns Hopkins said. "Nothing is going to happen to them, nor should it."