All are being silenced, none are being fired. Not a single one, they are all toeing the line. Those being fired have nothing to do with politics, they have run afoul of their own personal foibles: zippers, the bottle, ethics, money. The usual bane of human existence.
Those normal foibles are the cause in some cases, but there are others that are not so obviously rooted in some moral error on the part of the officer in question. And, of course, there is always the subterfuge that can be employed by misdirection: fire for one reason when the real reason goes unmentioned.