The FBI on Friday night raided the Sterling, Virginia, home of a Muslim convert, Sean Andrew Duncan, who, according to an FBI affidavit filed in the case, stated that he attempted to join ISIS in Syria and shared bomb-making instructions with a woman currently in international custody. Sterling, about 20 miles from Washington, D.C., is home to a large Muslim community. According to an Instagram post by Duncan, he converted to Islam at age 17 and moved to the area from Pittsburgh this past June. When reports emerged Friday night that an FBI raid was ongoing, there was no indication...