As the U.S. debates whether to intervene on behalf of the rebels fighting against Bashar al-Assad in Syria, evidence continues to mount that the resistance has adopted many of Assad’s brutal tactics. A new video leaked by a disaffected rebel shows his comrades performing a ritual execution of captured Syrian soldiers, teasing them before killing them with point-blank gunfire to the head. Across Syria, guerrilla fighter groups and criminal gangs have joined the rough rebel coalition. Secretary of State John Kerry has downplayed the role of Islamic extremists and other “bad guys” in the opposition, but U.S. representatives say their briefings on the war showed the opposition’s dark side more clearly.