Seymour M. Hersh has an excellent article about torture at Abu Ghraib in The New Yorker which can be accessed here. I will only paste a portion of the article, which is a quote of now retired Army Major General Antonio M. Taguba:
“There was no doubt in my mind that this stuff”—the explicit images—“was gravitating upward. It was standard operating procedure to assume that this had to go higher. The President had to be aware of this.” He said that Rumsfeld, his senior aides, and the high-ranking generals and admirals who stood with him as he misrepresented what he knew about Abu Ghraib had failed the nation.