The Islamic State of Iraq and the Levant (ISIS) used to have a different name: al Qaeda in Iraq.
US troops and allied Sunni militias defeated al Qaeda in Iraq during the post-2006 “surge” — but it didn’t destroy them. The US commander in Iraq, General Ray Odierno, described the group in 2010 as down but “fundamentally the same.” In 2011, the group rebooted. ISIS successfully freed a number of prisoners held by the Iraqi government and, slowly but surely, began rebuilding their strength.
ISIS and al-Qaeda divorced in February 2014. “Over the years, there have been many signs that the relationship between al Qaeda Central (AQC) and the group’s strongest, most unruly franchise was strained,” Barack Mendelsohn, a political scientist at Haverford College, writes. Their relationship “had always been more a matter of mutual interests than of shared ideology.”
According to Mendelsohn, Syria pushed that relationship to the breaking point. ISIS claimed that it controlled Jabhat al-Nusra, the official al-Qaeda splinter in Syria, and defied orders from al-Qaeda’s leader, Ayman al-Zawahiri, to back off. “This was the first time a leader of an al-Qaeda franchise had publicly disobeyed” a movement leader, he says. ISIS also defied repeated orders to kill fewer civilians in Syria, and the tensions led to al-Qaeda disavowing any connection with ISIS in a February communiqué.
Today, ISIS and al-Qaeda compete for influence over Islamist extremist groups around the world. Some experts believe ISIS may overtake al-Qaeda as the most influential group in this area globally.