On Nov. 1, 2010, a young Afghan approached Sgt. Felipe Pereira and his team on a shiny motorcycle near the end of a daily dismounted patrol. Pereira checked his pockets and bike for explosives, the soldier later told Stars and Stripes, and finding nothing, shook the rider's hand. The calm and collected Afghan smiled at Pereira, and as the squad turned away toward the base, the motorist detonated explosives hidden on his vehicle.