E.g. someone who was born in China, became a citizen of the USA, and renounced their Chinese citizenship would still never be allowed to work on ITAR. This is to prevent cases such as they steal some ITAR controlled info or materiel and flee back to China (and get their Chinese citizenship back as part of whatever espionage deal occurred).
Unfortunate for those who are truly passionate and have no malicious intent, but security comes first.
Parabolic arc site is 1001 right now, best I found was a dated WSJ article that precedes significant current reports & events:
edit:remove3d naive opinion.
Parabolicarc is now back online w/ a new site overhaul. This is the particular article that I was referring to:
http://parabolicarc.wpengine.com/2022/10/26/space-spacs-the-...