The following op-ed, Democrats and waterboarding, written by Harvard Law School Professor Alan Dershowitz, was published in the Wall Street Journal on November 7, 2007.

I recently had occasion to discuss the Bush administration’s war on terrorism with one of the highest ranking former officials responsible for planning that war. He asked me what I thought the administration’s biggest mistake was.

I told him that it was not immediately going bipartisan following the attacks of 9/11. President Roosevelt had invited Republicans to join his cabinet as the U.S. prepared to fight the Germans and the Japanese, and President Lincoln had included political opponents in his efforts to preserve the union. Creating a united political front against an external enemy may blunt the partisan advantage expected from a successful military effort, but it helps to keep the country together at a time when partisan bickering can undercut the effort. The former Bush official agreed, regretting that the war against terrorism had become essentially a Republican project.

Now the Democrats appear to be making the same mistake as they move toward what seems to be an inevitable retaking of the White House. Most of the Democratic presidential candidates are seeking partisan advantage from what many Americans see as the Bush failures in the war against terrorism and especially its extension to Iraq and possibly, in the future, to Iran.

This pacifistic stance appeals to the left wing of the democratic electorate, which may have some influence on the outcome of democratic primaries, but which is far less likely to determine the outcome of the general election. Most Americans — Democrats, Republicans, independents or undecided — want a president who will be strong, as well as smart, on national security, and who will do everything in his or her lawful power to prevent further acts of terrorism.

Hundreds of thousands of Americans may watch Michael Moore’s movies or cheer Cindy Sheehan’s demonstrations, but tens of millions want the Moores and Sheehans of our nation as far away as possible from influencing national security policy. That is why Rudy Giuliani seems to be doing surprisingly well among many segments of the electorate, ranging from centrist Democrats to Republicans and even some on the religious right.

It may seem strange that a candidate, who came to national prominence as the New York mayor, and one with a mixed record in that job, would be the choice of so many on security issues, despite his lack of experience in the national and international arenas. But the post- 9/11 Rudy conveys a sense of toughness, of no-nonsense defense of America.

I am not suggesting that Democratic candidates seek to emulate Mr. Giuliani. But they cannot ignore his tough stance on national security if they want to succeed in the 2008 election, as distinguished from selected state primaries. Marginal Democratic candidates certainly benefit from moving to the left on national security issues, but serious candidates — candidates who want to have any realistic chance of prevailing in the general election — must not allow themselves to be pushed, shoved or even nudged away from a strong commitment to national security.

Consider, for example, the contentious and emotionally laden issue of the use of torture in securing preventive intelligence information about imminent acts of terrorism — the so-called “ticking bomb” scenario. I am not now talking about the routine use of torture in interrogation of suspects or the humiliating misuse of sexual taunting that infamously occurred at Abu Ghraib. I am talking about that rare situation described by former President Clinton in an interview with National Public Radio:

“You picked up someone you know is the No. 2 aide to Osama bin Laden. And you know they have an operation planned for the United States or some European capital in the next three days. And you know this guy knows it. Right, that’s the clearest example. And you think you can only get it out of this guy by shooting him full of some drugs or waterboarding him or otherwise working him over.”

He said Congress should draw a narrow statute “which would permit the president to make a finding in a case like I just outlined, and then that finding could be submitted even if after the fact to the Foreign Intelligence Surveillance Court.” The president would have to “take personal responsibility” for authorizing torture in such an extreme situation. Sen. John McCain has also said that as president he would take responsibility for authorizing torture in that “one in a million” situation.

Although I am personally opposed to the use of torture, I have no doubt that any president — indeed any leader of a democratic nation — would in fact authorize some forms of torture against a captured terrorist if he believed that this was the only way of securing information necessary to prevent an imminent mass casualty attack. The only dispute is whether he would do so openly with accountability or secretly with deniability. The former seems more consistent with democratic theory, the latter with typical political hypocrisy.

There are some who claim that torture is a nonissue because it never works — it only produces false information. This is simply not true, as evidenced by the many decent members of the French Resistance who, under Nazi torture, disclosed the locations of their closest friends and relatives.

The kind of torture that President Clinton was talking about is not designed to secure confessions of past crimes, but rather to obtain real time, actionable intelligence deemed necessary to prevent an act of mass casualty terrorism. The question put to the captured terrorist is not “Did you do it?” Instead, the suspect is asked to disclose self-proving information, such as the location of the bomber.

Recently, Israeli security officials confronted a ticking-bomb situation. Several days before Yom Kippur, they received credible information that a suicide bomber was planning to blow himself up in a crowded synagogue on the holiest day of the Jewish year. After a gun battle in which an Israeli soldier was killed, the commander of the terrorist cell in Nablus was captured. Interrogation led to the location of the suicide bomb in a Tel Aviv apartment. Israel denies that it uses torture and I am aware of no evidence that it did so to extract life-saving information in this case.

But what if lawful interrogation failed to uncover the whereabouts of the suicide bomber? What other forms of pressure should be employed in this situation?

This brings us to waterboarding. Michael Mukasey, whose confirmation as attorney general now seems assured, is absolutely correct, as a matter of constitutional law, that the issue of “waterboarding” cannot be decided in the abstract. Under prevailing precedents — some of which I disagree with — the court must examine the nature of the governmental interest at stake, and the degree to which the government actions at issue shock the conscience, and then decide on a case-by-case basis. In several cases involving actions at least as severe as waterboarding, courts have found no violations of due process.

The members of the judiciary committee who voted against Judge Mukasey, because of his unwillingness to support an absolute prohibition on waterboarding and all other forms of torture, should be asked the direct question: Would you authorize the use of waterboarding, or other non-lethal forms of torture, if you believed that it was the only possible way of saving the lives of hundreds of Americans in a situation of the kind faced by Israeli authorities on the eve of Yom Kippur? Would you want your president to authorize extraordinary means of interrogation in such a situation? If so, what means? If not, would you be prepared to accept responsibility for the preventable deaths of hundreds of Americans?

Perhaps political campaigns and confirmation hearings are not the appropriate fora in which to conduct subtle and difficult debates about tragic choices that a president or attorney general may face. But nor are they the appropriate settings for hypocritical public posturing by political figures who, in private, would almost certainly opt for torture if they believed it was necessary to save numerous American lives. What is needed is a recognition that government officials must strike an appropriate balance between the security of America and the rights of our enemies.

Unless the Democratic Party — and particularly their eventual candidate for president — is perceived as strong and smart on national defense and prevention of terrorism, the Bush White House may be proved to have made a clever partisan decision by refusing to make the war against terrorism a bipartisan issue. The Democrats may lose the presidency if they are seen as the party of MoveOn.org, Michael Moore, Cindy Sheehan, Dennis Kucinich and those senators who voted against Judge Mukasey because he refused to posture on a difficult issue relating to national security. They will win if they are seen as just as tough but a lot smarter on how to deal with real threats to our national interests.

Mr. Dershowitz teaches at Harvard Law School. He is the author, most recently, of “Finding Jefferson: A Lost Letter, a Remarkable Discovery, and the First Amendment in an Age of Terrorism,” published this week by John Wiley & Sons.