As I left Yom Kippur services this year, standing on the steps of my temple, I looked across the street at your home, and thought: perhaps you will finally get us out of the torture business.

There is no more pressing moral issue facing the United States. Torture is a crime against humanity and it is a blatant violation of the most fundamental American ideal: that all humans are created equal and endowed with inalienable rights. In the previous administration, as is now well known, it became U.S. policy to trample on those rights-to destroy the dignity of prisoners of war, destroy their will, turn them into helpless animals, drive them to the edge of insanity, and torture them. Your administration is admirably committed to abolishing torture. But given the ambiguities, loopholes, secrets, and evasions that have obscured U.S. policy, we need a public accounting of the rules by which we will comport and constrain ourselves with prisoners of war. This has become necessary due to the obscene double-bookkeeping-by lawmakers and lawyers at their worst-by which we have laws that officially forbid torture but let it in through a back door by means of preposterous definitions and semantic wordplay. Torture is not allowed, but "enhanced interrogation techniques" are a different matter. These "enhanced techniques" have included torture by simulated drowning. Even to call it "waterboarding" is to contribute to an atmosphere in which it is permitted. It sounds like an activity at Club Med. Perhaps the name helps explain why top Democratic members of Congress who were briefed on this technique went along with it. It's as though the activity were OK, just so long as no one used the T-word. This is what moral depravity looks like: treating evil as something you can get around if you've got a good dictionary.

As I write, it has just been reported that John Brennan, a former top aide to George Tenet and one of your advisors on national security issues, has withdrawn himself from consideration for head of the CIA or National Intelligence. But look at the language the New York Times used to float this possibility. It says Mr. Brennan was "present at the creation" of the "controversial detention and interrogation program," but now he has "distanced himself" from that program. What do these mushy phrases mean? As if one needed one more sign of the decline of the Times, these phrases blur the most elementary moral distinctions. By reading them one cannot tell whether Mr. Brennan is a behind-the-scenes hero, whether he is trying to stop this moral outrage, or whether he is responsible for torture and crimes against humanity. Does "distance himself" mean follow Tenet's example and flatter whoever happens to be president? What exactly does one do when one "distances" oneself? Is that what Hitler is doing in hell-"distancing" himself from his attempt to exterminate the Jews?

Symbolic gestures-notably, closing Guantánamo Bay-are important, but they are not enough. We need to know what it means to be against torture. In effect, the policies of the past administration have placed two groups outside the rule of law: our torturers and their victims. It will be a huge challenge for your administration to bring these groups back into civil society. At the moment, the public knows there are "black sites"-another euphemism-but has no idea how many people are in them, how they got there, or what has been and is being done to the people in them. The overwhelming incentive for those who run these sites is not to let the prisoners out. Will the prisoners ever be accounted for? How? Will there ever be any fair evaluation of their guilt or innocence?

When it comes to torture, the country as a whole is in need of moral leadership. In the two-year period between 2006 and 2008, the percentage of the U.S. population favoring torture of suspected terrorists has jumped from 36 percent to 44 percent (according to the University of Maryland's Program on International Attitudes). Only 53 percent of our citizens support a ban on torture. That statistic probably influenced some members of Congress to turn a blind eye or implicitly condone the use of torture. The lesson should be the opposite. The statistic is evidence that, when it comes to the treatment of prisoners of war, we have lost our moral compass. One of the most important jobs of the president of the United States is to educate the American people, to help restore a sense of moral direction.

If you drive sixteen blocks due south from your home, you will come to the Oak Woods Cemetery. There you will find a mound-a monument to the approximately 5,000 Confederate soldiers who died as prisoners of war at Camp Douglas, which existed nearby on the south side of Chicago. They died not fighting the Union Army, but while in its custody. They died in appalling conditions of cholera, dysentery, gangrene, and starvation. Their names are listed along with their regiments. Here lie the remnants of bodies of men who died for ideals inimical to those of human equality and dignity that you and I share. Yet standing at the grave it is abundantly clear that they should not have died as they did. It seems to me that you have President Lincoln in your sights: that is the kind of historical stature to which you aspire. I suggest you take the family on a trip to that mound. In the treatment of our prisoners of war, there is one way you can outstrip Lincoln more or less immediately.

Jonathan Lear is the John U. Nef Distinguished Service Professor at the Committee on Social Thought and in the philosophy department at the University of Chicago.