That's not fair to the guy on the left. The guy being shot was an NVA spy, caught in enemy territory in civilian garb instead of a uniform. The Geneva Convention states that captured spies can be summarily executed, which is what is happening here. So this was perfectly legal, while we still don't know for sure about the Costco shooting (and I have my doubts).
Iconic photo - do you know the real story of this photo?
The (now) dead guy had just murdered the officer’s entire family just minutes before wife and children - I would have some the same.
Says a lot that his troops left the asshat alive for the boss to deal with him.....