USA or other Special Ops

[StainlessSteelCynic]

In addition to what Swaghauler mentioned...
During the 1990s there was one moderately accurate way to identify some US SOCOM guys... chewing tobacco.
Chewing tobacco never had the same popularity in other parts of the world and when they were in civvies, I was able to spot the US guys amongst Aussie, British and New Zealand special forces types with about 75% accuracy based on who smoked cigarettes and who used chewing tobacco.