"The inhalation brought the damp cloths tight against my nostrils, as if a huge, wet paw had been suddenly and annihilatingly clamped over my face."

Christopher Hitchens has himself waterboarded.

Unable to determine whether I was breathing in or out, and flooded more with sheer panic than with mere water, I triggered the pre-arranged signal and felt the unbelievable relief of being pulled upright and having the soaking and stifling layers pulled off me. I find I don’t want to tell you how little time I lasted.

He has a second go at it:

Steeling myself to remember what it had been like last time, and to learn from the previous panic attack, I fought down the first, and some of the second, wave of nausea and terror but soon found that I was an abject prisoner of my gag reflex. The interrogators would hardly have had time to ask me any questions, and I knew that I would quite readily have agreed to supply any answer. I still feel ashamed when I think about it....

Hitchens concludes: "[I]f waterboarding does not constitute torture, then there is no such thing as torture." But if Hitchens is willing to submit to it as an experiment, it can't be the worst torture. We can easily think of many tortures that he would not have accepted for journalistic purposes and that no one friendly to him would have perpetrated.

Hitchens doesn't deprive us of the pro-waterboarding argument:

[A] man who has been waterboarded may well emerge from the experience a bit shaky, but he is in a mood to surrender the relevant information and is unmarked and undamaged and indeed ready for another bout in quite a short time. When contrasted to actual torture, waterboarding is more like foreplay. No thumbscrew, no pincers, no electrodes, no rack. Can one say this of those who have been captured by the tormentors and murderers of (say) Daniel Pearl? On this analysis, any call to indict the United States for torture is therefore a lame and diseased attempt to arrive at a moral equivalence between those who defend civilization and those who exploit its freedoms to hollow it out, and ultimately to bring it down. I myself do not trust anybody who does not clearly understand this viewpoint.

But Hitchens nevertheless concludes that it is torture and that Americans should not torture, and his argument is chiefly a practical one premised on American interests.

ADDED: Video of the Hitchens waterboarding.