In theory, such a gun could have prevented the Sandy Hook school massacre in Newtown, Conn. Adam Lanza used weapons purchased by his mother to kill her and 26 children and school staff.’ Sorry, I couldn’t resist. Word arrives that, not for the first time, a starry-eyed entrepreneur is planning to market an “intelligent” weapon. According to The Wall Street Journal, “ the new weapon is the Colorado startup Biofire’s 9mm Smart Gun, which can only be fired if it recognizes an authorized user with a fingerprint reader on the grip or a facial recognition camera on the back.” Advertisement...