A Question for Conservatives

Throughout history the practice of torturing captives has been commonplace in societies ranging from primitive tribes to higher civilizations. Under the influence of liberal and enlightenment ideas, torture was banned in much of European civilization during  the period  from the mid-1600’s to the early 1800’s, and its continued use in  the Middle East, east Asia, and perhaps Russia was seen as evidence of a residual barbarism in those societies.   By the beginning years of the 20^th Century the article on torture in the Encyclopedia Britannica was able to say that “the whole subject is now one of only historical interest as far as Europe is concerned “.  Of course the later rise of fascism and communism in that century proved the author wrong as European civilization experienced  a terrible reversion to barbarism.  

Torture was never legal in the United States, but last week Americans were reminded by a report from the US Senate that people in their government have resorted to torture in interrogating Muslim  prisoners suspected of being terrorists. I agree with those who oppose torture on ethical grounds and believe its use to be barbaric and to have no place in a free and civilized society.  

A number of conservatives have defended the practice.  I have a question for them. Many of them claim to revere the constitution. The constitution explicitly bans both inflicting cruel and unusual punishments and forcing a person to give criminal testimony against himself.  Ethical questions aside, how can self-proclaimed constitutional conservatives defend its use  it the light of that alone?