The third factor was the feckless and incompetent rule of then-Iraqi
Prime Minister Nuri al-Maliki, who marginalized Sunnis and
disenfranchised them from Iraq's political process to the point that
many Sunnis preferred the rule of the Islamist militants in ISIS to that
of the "Shia" government in Baghdad. Inexplicably, the Obama White
House kept backing Maliki despite his manifest flaws as a leader.
-- Peter Bergen, "Did Barack Obama and Hillary Clinton create ISIS?" (CNN).