Here's a lesser-known set of facts leading to the creation of ISIS:
John Kerry was actively wooing Assad until early 2011 when the Petraeus-Clinton faction took control over MENA policy, and regime change was brought simultaneously to Syria, along with Libya and Tunisia. The project was most aggressively led on the ground by covert operators from France and Qatar, to a lesser extent involving the U.S., U.K., Saudi Arabia, UAE and Turkey in funding, coordination, propaganda, logistics and support. Ongoing programs run by CIA and State Dept. were ballooned, and there were a lot of meetings, but mostly we watched civil war unfold as third-force special forces units (mostly Qatari) led armed uprisings in Libya and Syria. In March 2011, President Obama signed a classified "finding" coordinating efforts with Qatar and several other countries to overthrow Qaddafi.
http://www.reuters.com/article/2011/03/30/us-libya-usa-order-idUSTRE72T6H220110330 A similar directive was signed ordering similar covert operations in Syria.
In April, 2011, Chris Stevens arrived in Eastern Libya where he took a lead role in organizing opposition militia. At the time of Stevens death on September 12, 2012, Ghadaffi had been killed the previous October after retreating to his tribal homeland in Sirte, and the Libyan army had dissolved. Opposition militia were in charge of the rest of the country and arms stocks. By that stage, there was an active pipeline set up for Islamic fighters and looted Libyan heavy arms -- along with shoulder-fired antiaircraft missiles (MANPADs) -- flowing into Syria by way of Turkey. That movement of MANPADs was first confirmed in a Times of London article published two days after the attack on the US compound in Benghazi. See,
http://www.dailykos.com/story/2012/09/28/1137620/-Times-of-London-Shipload-of-Looted-Missiles-From-Libya-Arrives-in-Turkey#
The death of Stevens and the spread across the region of heavy arms and Jihadist Libyan fighters armed and trained by Qataris using Saudi and Gulf money forced President Obama to reconsider the policy. CIA Director Petraeus, who was confirmed in September 2011 to succeed Leon Panetta, resisted winding down the operation. In a showdown White House meeting the following October, Petraeus was supported by Secretary of State Clinton and Defense Secretary Panetta. Obama's decision to wind down what has been referred to as "Operation Zero Footprint" came after discussions with national security advisor Tom Donilon. The rift within the Administration was first made public during Senate hearings the following February. See,
http://www.nytimes.com/2013/02/08/us/politics/panetta-speaks-to-senate-panel-on-benghazi-attack.html?_r=0 Petraeus' ongoing affair with his biographer was exposed, and Secretary Clinton's resignation graciously accepted after the Inauguration. The rest, as they say, is history.