From an op-ed piece in Monday’s Roanoke (Virginia) Times: Last month, federal agents in Maryland arrested a United States Coast Guard officer and said he was plotting to assassinate Democratic members of Congress, prominent television journalists and others. The officer, Lt. Christopher Hasson, apparently inspired by a right-wing Norwegian terrorist who slaughtered 77 people in 2011, stockpiled firearms and ammunition and researched locations around Washington to launch his attacks, according to investigators. Fortunately, the F.B.I. arrested him before he could act.When news came of Hasson’s arrest, President Trump– who has no problems expressing the fiercest outrage at Democrats and even...