In the video of the interview with Joshua Landis that I posted on the Syria thread yesterday he touches on some of the previous relations between the FSA and the Daesh, particularly in the taking of the Menagh Air Base: http://youtu.be/_-roW5Y7vbw?t=19m11s He mentions the propo video Flames of War by way of evidence. I won't link to the video, which is easily enough found by any search engine.
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