I think this is the most detailed and credible report I've seen on how coercive techniques became standard in our GWOT. It names the names, it gives the dates, and it's full of verifiable and/or disprovable specifics.

If your aim is to destroy a detainee's sense of self and humanity, using primarily psychological tools, I guess you can dance around whether or not "torture" is the correct word. Doesn't matter, really. The damage done to our prestige and moral capital is incalculable.