what do these clear rules and laws say about the following? - US blows up various hospitals because "may contain insurgents" - US blew up US citizen + his chi

what do these clear rules and laws say about the following? - US blows up various hospitals because "may contain insurgents" - US blew up US citizen + his child without due process because "terrorism" - US sanctions countries it doesn't like, causing civilians to starve/suffer/lack medicine seems evident to me that one party doesn't really follow "the rules". how come they have a permanent seat at the UN security council? what punishment is prescribed for rule breakers? because it clearly isn't any loss of influence/prestige/sanctions/etc.