Daniel W. Drezner is a professor of international politics at the Fletcher School of Law and Diplomacy at Tufts University and a regular contributor to PostEverything.

Senate Intelligence Chairwoman Dianne Feinstein (C), a Democrat from California, speaks to reporters about the committee’s report on CIA interrogations at the Capitol in Washington, D.C., Dec. 9, 2014. The CIA’s interrogation of al-Qaeda suspects was far more brutal than acknowledged and did not produce useful intelligence. Both of these conclusions will be necessary to make sure this does not happen again. (Saul Loeb/AFP)

In the day since the Senate’s report on U.S. torture has been released, the debate has already spilled out into a myriad array of smaller debates, ranging from just how much former CIA Director Michael Hayden misled Congress to the precise forms of (horrific) torture subjected on U.S.-held captives to what President Obama should do now — and I just had to go to The Washington Post’s front page for that.

Still, some are dissatisfied with aspects of this debate:

Now I get why Greenwald wants the debate to be about the inherent immorality of torture. The trouble with debating torture’s efficacy is that if it turns out that information extracted from torture can be tactically useful, then advocates will be able to make their case more effectively in public discourse. On the other hand, if the debate takes place strictly on the moral and ethical plane, anti-torture advocates will feel on firmer ground.

I wholeheartedly agree with Greenwald et al that torture is inherently wrong. I’m embarrassed and ashamed as an American by the CIA actions documented in the Senate report. But I also want to partially defend debating its efficacy. Because I don’t think the development of taboos is as simple as Greenwald wants it to be.

International relations scholars have written a fair amount about how norms are created in world politics. And the messy truth is that there are a number of mechanisms through which certain actions become taboo. To be sure, part of it is the internalization of the idea that a certain action is inherently wrong. But power and interest have their roles as well. The slave trade was extinguished not just because certain Britons found the practice repugnant, but because the Royal Navy was powerful enough to make British policy preferences matter. The norm against the first use of nuclear weapons came about for a variety of reasons, including the impracticality of using nuclear statecraft to achieve ordinary foreign policy goals.

In both cases, the initial reasons for banning a particular practice were variegated. It is only with the passage of time that the power of these taboos increases through the internalization of the idea that slavery or nuclear first-strikes are wrong, wrong wrong. At the outset, however, the emergence of these norms had just as much to do with power and interest as with the moral power of their ideas.

Which brings us back to torture.

As much as Greenwald and I want it to be a taboo in the United States, it clearly isn’t. The United States practiced torture within the past decade. Furthermore, Americans are not opposed to torture so much as ambivalent about it. My Washington Post colleague Aaron Blake notes Wednesday that American public opinion is all over the map on this issue:

Tuesday’s report was released by outgoing Senate Intelligence Committee Chairwoman Dianne Feinstein (D-Calif.) to move the needle on torture/enhanced interrogation techniques in hopes of averting future use of such techniques. But that effort is severely complicated by a very mushy middle of the American public that offers wildly different thoughts on torture.

The “very mushy middle” might have moral qualms about torture, but still think it’s justified in extreme circumstances. It’s possible they’ve come to this conclusion based on “24” and “Zero Dark Thirty” rather than any real policy debate. The point is, these are the people who need to be persuaded that even in extreme circumstances, torture is useless because it doesn’t work at extracting useful information. It is through developing a public consensus on this issue that a norm starts to take effect — and, hopefully, policy practitioners internalize that belief.

This means, by the way, a full debate about the total costs and benefits of torture, not just whether it “works” as narrowly defined. For example, Marcy Wheeler has written forcefully about the dangerous ways in which torture allows for officials to manufacture the information they want to use to justify their pre-existing policy preferences. That’s another powerful argument against torture, even though it’s a pragmatic one rather than an ethical one. It needs to be mentioned more often.

A generation from now, I hope Greenwald is correct and any vestigial debate about torture is confined to ethics classes in philosophy departments. In the here and now, however, the practical debates will have to take place. That’s necessary to nudge Americans toward the disapproval of torture that Greenwald and I share.