The failure of psychology?

I was amazed to listen to this interview on NPR of a psychologist with the US military the other day. He makes no apologies for others using psychology to torture detainees and argues that it is a duty to use his knowledge of human psychology in any way necessary to protect America.

Obviously he does not represent all psychologists, especially not civilian psychologists. His nationalist fervor though was quite striking.

This got me thinking about other social scientists using their knowledge to "help" America. What if an economist was asked to plunge a nation into economic catastrophe? (For instance, see Confessions of an Economic Hit Man)

Never mind that it may produce results counter to American security to economically destroy a nation, or that it would be wrong to, say, ensure people starve. When are professionals, academics even, allowed to commit evil in order further a nations interests? Are they as guilty as the torturers themselves, or even more so since they (should) know better than anyone the consequences of what they are doing?