Federal and state officials revealed yesterday that they had thwarted a plot to kidnap Michigan Gov. Gretchen Whitmer, unsealing charges against 13 people who they say were involved in various plans to attack law enforcement, overthrow the government and ignite a civil war. Officials said the conspiracy — which was supposed to come to fruition before the election — seemed to be an ominous indication of how America’s civil unrest has energized violent extremists. The plotters, according to an FBI affidavit, seemed to be motivated at least in part by their...