House Republicans are calling on Homeland Security Secretary Janet Napolitano to step down or be fired in the wake of a controversial department memo that has sparked indignant battle cries from conservatives and some veterans. “Singling out political opponents for working against the ruling party is precisely the tactic of every tyrannical government from Red China to Venezuela," said Texas Rep. John Carter, a member of the party's elected leadership who has organized an hour of floor speeches Wednesday night to call for Napolitano's ouster. “The first step in the process is creating unfounded public suspicion of political opponents, followed...