Those are people empowered by society with the right and responsibility of making those choices, and under certain specific guidelines. Generals cannot bomb whomever they want, and Judges cannot condemn anybody they want–not and remain Generals and Judges, at least. What you’re advocating is vigilante law, a complete breakdown of the rules of society, and a jungle law where the strongest man or the man with the biggest weapon or the quickest trigger-finger is “right.” Forgive me, but I don’t think that’s heroism, or even in any way sensible.