How could this attitude lead to abuse?

BBC News has an interview with General Janis Karpinski, the one in charge of MPs at Abu Ghraib during the abuse. She continues to claim she is a scapegoat in the whole thing and knew nothing about what occurred, a problem in itself. But she went on to drop this nugget from her leadership.

She said current Iraqi prisons chief Maj Gen Geoffrey Miller - who was in charge at Guantanamo Bay - visited her in Baghdad and said: "At Guantanamo Bay we learned that the prisoners have to earn every single thing that they have."

"He said they are like dogs and if you allow them to believe at any point that they are more than a dog then you've lost control of them."

In effect, treat them like dogs. Awesome.