Remind me again, why is the United States backing a rebel force that uses suicide bombers? (Reuters) Rebel suicide bombers struck overnight at an Air Force Intelligence compound on the edge of the Syrian capital Damascus, killing or wounding at least 100 people, insurgents and activists said on Tuesday. The militant Islamist group al-Nusra Front said it had mounted the attack because it was used a center for torture and repression in the crackdown on the 18-month-old revolt against President Bashar al-Assad. Big shockwaves shattered windows and destroyed shop facades. It felt as if a bomb exploded inside every house in the area, said one resident of the suburb of Harasta, where the compound was located. Activists living nearby said the bombing caused at least 100 casualties among security personnel, based on the number of ambulances that rushed to the scene and the enormity of the explosions.