OSTON, March 13 — Their friends are horrified. Even they are surprised at themselves. But as the nation stands on the brink of war, reluctant hawks are declining to join their usual soulmates in marching against war.

Across the river in Cambridge, often considered a bastion of liberalism, supporters of military intervention in Iraq include the dean of Harvard's John F. Kennedy School of Government — putting him at odds with many colleagues. At the University of California at Berkeley, Cambridge's West Coast twin, the dean of the graduate school of public policy also counts himself in the pro-war camp.

In Washington, former Clinton administration officials who opposed the first Persian Gulf war are now making arguments for another one.

And Elie Wiesel, a Holocaust survivor and Nobel peace laureate, emerged from a meeting with President Bush last month and declared that while he is "not a man of war," he supports it as a way to stop Saddam Hussein.

It is not that the war is a litmus-test issue. Many of the Democratic presidential contenders voted for the Congressional resolution last year authorizing the president to use force against Iraq. But Democrats are more divided than Republicans over the war, polls show, which has led to a sometimes uncomfortable split in the ranks of the left in particular.

Those who have decided to shun the antiwar movement do not claim their positions without reservation — particularly as the Bush administration remains at stark odds with its traditional European allies.

Some among them say they would prefer more diplomacy, more support from other nations, more time. And their reasons for supporting military intervention vary: concerns about weapons of mass destruction that might be used against this country, or against Israel, a rethinking of America's role after Sept. 11 or a general belief that intervention is the humanitarian response that will improve the lives of the Iraqi people.

But they unite in a belief that Mr. Hussein must be removed from power.

If they will not call themselves hawks, they express impatience with what they see as a lack of nuance among the antiwar protesters.

"It's something of a scandal in my eyes that hundreds of thousands of people are not marching in support of the oppressed Iraqis," said Paul Berman, a New York writer and cultural critic, whose forthcoming book, "Terror and Liberalism," advocates aggressive intervention to promote democratic ideals.

No one should be surprised, said Mr. Berman — also the author of "A Tale of Two Utopias: The Political Journey of the Generation of 1968" (W.W. Norton and Company, 1997) — to see some of the same people who opposed the Vietnam War in their youth now supporting a war in Iraq. In both cases, he argues, the impulse was humanitarian.

Michael Ignatieff, the director of the Carr Center for Human Rights at Harvard and a contributing writer for The New York Times Magazine, agreed, and pointed to the dangers posed by Saddam Hussein.

"Liberals are always accused of equivocating and splitting differences, but this guy really is awful," Mr. Ignatieff said of Mr. Hussein, explaining why he has joined the ranks of the reluctant hawks. "But I'll tell you, it's extremely unpopular among my friends."

Bosnia, too, reshaped their thinking.

"Being antiwar and antiuse of force was a kind of defining signature of being a liberal, but that was 30 years ago," Mr. Ignatieff said. "In the 90's, being a liberal meant being in favor of military intervention in Bosnia and Kosovo. Human rights has come into this and complicated the picture considerably."

Another pocket of somewhat hesitant backers of military might can be found among former Clinton administration officials who say they have become increasingly concerned about weapons of mass destruction.

"The rogue states are doubly dangerous, because they not only have these weapons themselves and could use them on their neighbors, but they could at any time hand them off to others who could use them," said Michael Nacht, an assistant director at the Arms Control and Disarmament Agency in the Clinton administration and now dean of the Goldman School of Public Affairs at Berkeley. "I don't think it's hyped. I don't think it is purely for political reasons. I think it is real."

Kenneth Pollack, another former Clinton administration official, laid out his case for war in his book "The Threatening Storm," published last fall by Random House. "The choice we have before us is we either go to war now or we will never go to war with Saddam until he chooses to use a nuclear weapon and he chooses the time and place," Mr. Pollack said in an interview this week. "The question for me is not war or no war. It's a question of war now, when the costs may be significant, or war later when they may be unimaginable."

Mr. Pollack said his conversion began in the late 1990's, when he and other administration officials began to believe that containment was not working in Iraq. They decided that the only way to stop Iraq's development of weapons was to get rid of Mr. Hussein and that the only way to get rid of him was through war.

Now, Mr. Pollack said, "Any number of my colleagues and former bosses are where I am."

Joseph Nye, the dean of the Kennedy School, has written extensively about the importance of the "soft power" of a nation's cultural and diplomatic influence, as opposed to the hard power of military might. Opponents of war in Iraq have used that concept to argue their case. But Mr. Nye, who supported the first Persian Gulf war, says he has come to believe that alternatives to military action have failed.

"Hard power can complement soft power," he said. "The people who say that any war at all is bad for our soft power are placing the trade-off in a different place than I am. When weapons of mass destruction are an issue, I think you can make an issue for war."

Others who are not joining the ranks of protesters say they base their reluctant support for Mr. Bush at least in part on their concerns about Israel.

"Israel was not in the gulf war, but all of a sudden he began dropping Scud missiles on it," said Mr. Wiesel, who is also a professor at Boston University. In an opinion piece in The Los Angeles Times this week, Mr. Wiesel wrote that he would ordinarily choose to march against war, but that in this case he cannot bring himself to do so.

"If those who march were to say, `Down with Saddam, no to war,' that would be another thing," he explained in an interview this week. "But to forget who Saddam is, what he has done — he should have been stopped ages ago."

Still, Mr. Wiesel would not go so far as to call himself a supporter of war. Among the reluctant hawks, ambivalence takes many forms. Those primarily concerned with human rights struggle to weigh which cost is higher: the lives inevitably lost in a war, or the lives of the Iraqis they say Mr. Hussein kills each year.

Mr. Berman criticizes President Bush for failing to appeal to liberals in the Arab and Muslim world who could help establish a new government in Iraq as a model for democracy in the Middle East and for failing to emphasize the human rights concerns used to support military intervention in the Balkans.

Mr. Nye argues that the United States could have gone to war before offering the current United Nations resolution, based on Mr. Hussein's failure to satisfy earlier resolutions. But now that the United Nations is wrangling over a new resolution, Mr. Nye, like others, argues for more time to build a broader coalition.

And Mr. Pollack, whose book has become something of a guide for those supporting war, argues that those who use him to bolster the Bush administration's case have focused too much on its subtitle, "The Case for Invading Iraq," and not enough on the conditions it sets for intervention, a weakened Qaeda, a broad coalition, putting Mideast peace negotiations on track.

Michael Walzer, at the Institute for Advanced Study in Princeton, the author of "Just and Unjust Wars," argues for a smaller-scale use of military force than the Bush administration plans, short of all-out war. His doubts are such that he says, "If I had to plunk, I'd plunk against war."

Still, he says he is too uncertain to join the marchers against the war.

"It's because Saddam is really a fascist regime," Mr. Walzer said. "I think there are a lot of people in my position who want to do something about that. And they wish the marchers were marching for that, as well."