it's good work if it helps the right people

Who are the "right" people to kill? What happens when govt decides to aim your weapons at the "wrong" people?

the people who are invading another country in a war of conquest, for instance

you seem to believe we live in a world where there no longer are such wars of single-handed aggression

we don't live in that world

Right. Not knowing human nature doesn’t mean you won’t be affected by it in ways that you just haven’t thought of or don’t believe could happen to you.

> a war of conquest

Israel invading Gaza is kind of proving the point? Those are American weapons bombing civilians.