I was a bit surprised to find that my blog post on Hans Joachim Scharff was two and a half years old already. Since then, the articles it refers to have vanished, and the centre of gravity of the political debate on torture in the US has shifted from labeling the sadistic scum humiliating prisoners at Abu Ghraib as "a few bad apples" to "anti-torture" being a political label for those who pretend to put up a fight against the legalisation of torture in all but name, rather than a minimal precondition for membership in democratic society. So I'd like to link to it again, and also recommend Katherine and Hilzoy's many posts on the issue at Obsidian Wings as just a starting point for those who want to know more about what is being done in Americans' names.
One article that I found in a new search for "Hans Joachim Scharff" is Truth Extraction: Honey Beats Vinegar which also describes how one American interrogator got useful information out of Japanese prisoners of war by ensuring they felt safe. That links to a longer article which is unfortunately behind a subscription wall.