Everyone that leaves the service with a TS or better clearance gets to keep it active for 5 yrs after leaving. Don't know what the req's are for anything above a TS/SCI. Mine was active for 10 yrs after I got out, plus I got to sign a lifelong gag order on what I trained in/on/with and ALL ops I was involved in, PLUS ALL intel I consumed or was within earshot of. AND a nice little red flagged FBI file because I played with explosives and was privy to highly sensitive msg traffic as I was me units msg handler, too.  I don't think McChrystal has been out for more than 10 yrs. I also know that most guys like him go in/out of public service after retiring, so often in fact, that their clearance is hardly ever able to lapse into inactive status like mine is currently. When I got out, it was after some major redpill moments, so I happily let it go. Haven't been in any kind of work to need one again. I left that up to the [DS] types. Couldn't stomach the Fed shit under Bush/Hussein.  I kinda wish I had stayed in the govt after '04 so I could have a better working knowledge of what [they]'be been doing for theblast 16 yrs. I still get information from friends, but it's not the same as reading 100's of msgs.