Is being a mercenary illegal?

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Tags

1. #banning
2. #report
3. #activity
4. #united
5. #states
6. #mercenary
7. #international
8. #countries
9. #kingdom
10. #signatories
11. #nations
12. #under
13. #found
14. #including
15. #mercenaries
16. #contractors
17. #blackwater
18. #illegal
19. #convention