First Amnesty International, now the Red Cross:

The international Red Cross says the abuse it found in Iraq's US-run prisons was systematic and amounted to torture, adding that it first raised concerns with the United States more than a year ago. At a quickly-arranged news conference, the International Committee of the Red Cross' director of operations, Pierre Kraehenbuehl, said US authorities had broken international laws and their transgressions had been documented in an ICRC report. "The elements we found were tantamount to torture... There were clearly incidents of degrading and inhuman treatment," he told reporters.

Democracy of One writes that the Bush Administration's culture is responsible for the abuse of Iraqi prisoners:

It is the contempt for due process and civil liberties by Bush and other administration officials that has led to the culture of impunity under which these abuses have occurred. The culture of any organization starts at the top, and lower ranking members take the lead from those above them. In the administration’s bluster to protect America by suspending civil liberties, they unwittingly fostered an environment where gross violations of international law and human decency were tacitly, though not explicitly condoned. While direct orders from top military brass surely were never given to rape, murder and sexually humilate prisoners, these acts are the result of administration policies that lack transparency and accountability