Other side
When I was a USMC Sgt in charge of the FLIR/Laser intermediate level Avionics repair shop in MCAS El Toro, CA in 1985-1989, one of my best men was one of those despised "Mercenaries"!
CPL Bray (known as "Blackie", of course) was not a US citizen (although his older brother was). This was made clear in Dec. 1986, when he tried to go visit his parents for Christmas leave and his request was denied.
His statement to the CO of Headquarters & Maintenance Squadron 13 was:
"I don't care if Éire (Republic of Ireland) IS on the DOD's "Restricted Travel" List, if you won't let me go home to see my parents, then I'll have to have MY Ambassador talk to YOUR President on the subject! Now, can we solve this here, like fellow Marines should?"
He got to go home, but had to "recieve" a "security briefing" from G-2 (Intelligence) first. The spook Major said "I learned more about the current situation in Ireland from that CPL than in my last official update"!
He served with honor, and went where he was sent, so we all had nothing but respect for him!