In 1973, Col. Yosef Alon, an Israeli military attaché, was gunned down in front of his home in suburban Maryland. The gunman was never identified despite an extensive F.B.I. investigation.In 1973, Col. Yosef Alon, an Israeli military attaché, was gunned down in front of his home in suburban Maryland. The gunman was never identified despite an extensive F.B.I. investigation.