My security clearance ended when I retired honorably. Why should these anti-American criminals be allowed to keep theirs?
I know mine will be when I retire.
My guess would be if they become a lobbyist.
One of the perks when you reach a certain level in gov.
What you lost at your ending debrief was your accesses.
Most likely you got to sign non-disclosure documents listing the severe penalties for violations. Depending on your accesses you might also have had to sign publishing restrictions and/or travel restrictions.