You just do not understand how works the Power in democracy. It's not in the hands of the guy you see on TV.
The foreign policy is mainly decided by the CFR. And their decision and plans must be approved by the Senate. But who cares about these guys as long as you don't see them on TV hmm ?
Most of the ISIS leaders have been formed and employed by NATO in Libya against Khadaffi. Then they were sent (with their fighters) In Turkey to fight Assad. They've recruited european djihadist and some Chechens, Bosniac and Afghans. At this moment, it was a "classic" Al Qaeda commando.
In 2014 they've released some hostages. Those hostages said they've seen some french, saoudi and american officer. Then they retracted their testimony.
The problem with the new Iraq, is that it sell half of his oil production to China, with the help of Iran. Iraq received weapons from Iran despite the US embargo (on Iran), for exemple.
The division of Iraq in 3 parts (CFR/Joe Biden's plan) has been approved by the Senate in 2007.