It’s not only permissible but “likely valuable for retired officers to weigh in on public debates on controversial issues, like gender integration or proposed military action, where it would be inappropriate or difficult for serving generals to weigh in where their civilian masters have spoken.” Certainly, things like the propriety of revocation of security clearances for reasons unrelated to trustworthiness or the integrity of the Russia investigation fall within that ambit.

Additionally, I concur with RAND scholar and Bombshell co-host Radha Iyengar Plumb that McRaven and the signers of the open letter spoke out in “reaction to abuse of political power in a national security context” and that this is mere “defending institutional norms” vice partisan politics. While taking on a sitting president is inherently political, as nonpracticing professionals their oath to defend the Constitution against all enemies—foreign and domestic—remains in force.

James Joyner is a security studies professor at the Marine Corps Command and Staff College and a nonresident senior fellow at the Brent Scowcroft Center on International Security at the Atlantic Council. These views are his own.