The national-security protest letter-writing campaign continues, with 175 former top U.S. officials rebuking President Donald Trump for stripping former CIA chief John Brennan of his security clearance last week. “Our firm belief is that the country will be weakened if there is a political litmus test applied” before seasoned professionals can share their unclassified views, the new batch of signers wrote. They include Nick Rasmussen, the former National Counterterrorism Center director; former Deputy Secretary of State William Burns; former National Security Adviser Anthony Lake; more than 10 former U.S. ambassadors, and more than 20 former U.S. Attorneys. The latest missive follows one last Thursday, when 15 former directors and deputies from the CIA and Office of the Director of National Intelligence voiced their objections. A day later, 60 former senior CIA officials added their names, said former CIA spokesman Bill Harlow. “Over the weekend, the organizers of the initial messages were inundated with requests,” from senior officials who “wanted to speak out against treating security clearances like political party favors.” Trump has threatened to strip clearances from a half-dozen other former officials and one who is currently serving at the Justice Department. —Kimberly Dozier