
Khalid al-Hamad, left, in an undated photo that originally appeared on the website of the Syrian rebel group, the Independent Omar al-Farouk Brigade, which he commands.
In a conflict that has already yielded too many scenes of graphic horror, it takes a mere 27 seconds of video footage to plumb new depths of depravity. Posted on YouTube, the video opens with a rebel commander named Khalid al-Hamad, who goes by the nom de guerre Abu Sakkar, holding a knife as he bends over the body of a dead soldier. There's a gaping hole in the soldier's chest. First al-Hamad transfers what appears to be the dead man's heart onto a flat piece of plastic or metal lying on the soldier's stomach. Then he pulls what looks like...