The denial of human rights in American prisons after Iraq's invasion, provided a unique setting for radicalization and creation of the Islamic State.

Guantanamo Bay detention camp

After the disgraceful invasion of Iraq, American prisons provided a unique setting for both prisoner radicalization and inmate collaboration — and was formative in the development of today’s most potent jihadist force. In all, nine members of the Islamic State’s top command did time in one of them, at Bucca. These prisons became virtual terrorist universities: the hardened radicals were the professors, the other detainees were the students, and the prison authorities played the role of absent custodian. So, from the ashes of what former inmates called an “al-Qaeda school” rose the Islamic State. 

Source: https://www.washingtonpost.com/news/morning-mix/wp/2014/11/04/how-an-american-prison-helped-ignite-the-islamic-state/

Do you know that Abu Bakr al-Baghdadi was detained by the Americans before to become the leader of the so called Islamic State? The denial of human rights doesn't pay.