Acting defense secretary Christopher C. Miller ordered the director of the National Security Agency to install on Saturday a former GOP political operative as the NSA’s top lawyer, according to four individuals familiar with the matter. The move is troubling, coming as it does four days before President Trump leaves office and the Biden administration takes over, former U.S. officials said. The move makes it more difficult for the Biden administration to immediately replace him, the former officials said. “An 11th-hour move like this and a directive from the acting secretary of defense is overwhelmingly strong evidence of irregularity,” Hennessey...