United States firearm sales have sky-rocketed since the Newtown school massacre, as debate over gun control rages and enthusiasts fear certain assault weapons and high-capacity magazines could be banned. President Barack Obama basically has put gun enthusiasts on warning, Larry Hyatt, owner of a gun shop in Charlotte, North Carolina, told AFP, referring to efforts to outlaw certain weapons in the wake of the Newtown shooting. A semi-automatic Bushmaster AR-15 assault rifle was used in the Sandy Hook Elementary School massacre in which a disturbed local young man shot dead 20 young children, six adults and his mother before taking...