I was in the Army Security Agency in the US Army. I observed NCO’s and Officers lose their clearances because of marital affairs, a DUI, a fight, etc. I took my clearance seriously. I had a TS/SBI/TK1. It would have been a cold day in hell that I would have let anyone without a clearance see one of those documents. Because I would have been court-martialed and sent to Leavenworth. And, because I gave my word of honor. And I signed documents as my testimony. I guess people like Hillary could care less about honesty, integrity, and accountability.
For FReepers unfamiliar with how classification works, it's always possible for anyone with a clearance to determine whether something you're reading or writing is classified and to what level and caveat. Classified guidelines are written stating very clearly that association of this weapon with that country has this level of classification, etc. The guidance is clear and easy to understand, and if you have any questions, there are security officers who can answer them.
I was going to enlist in the ASA but was blocked from doing so because my step mother had a brother in East Germany. I never gave it a thought and didn’t ever say anything but they sure found out.