Senior Executive Service:
Established by Carter c. 1988. Non-merit-based. Bypasses civil service salary restrictions. Virtually immune to Congressional oversight or Presidential authority. Increased by Obama from under 2000 to over 8000 in 2016 - just in time to thwart Trump with almost literal impunity.
Almost all key players in slow-motion coup are SES - or the equivalent sister organization in other bureaus (including Five Eyes!).
Some call it Obama’s Army. I call it Deep State Central. Think Hydra embedded in SHIELD in MCU.
Carter was in office 1976 -1980.
It was created in 1979 when the Civil Service Reform Act of 1978 went into effect under President Jimmy Carter.
https://en.wikipedia.org/wiki/Senior_Executive_Service_(United_States)
Most serve at the pleasure of the executive. Unfortunately few to no past executives have exercised that authority!
Protocol-wise they are the equivalent of military flag officers.