> So a dictator can invade any country he wants
Let me guess: You live in the US.
For most people in the world, the situation is that the US, and possibly some neighboring regional power, can invade whenever they want; and at best we can offer limited initial resistance and guerilla/terrorist attack once they've occupied.
But "with food comes appetite": The US government has normalized, among its citizens, the presumption of military intervention where and when it likes. That is deplorable. What's worse, though, is that it can stretch the same trick as far as nuclear war. That is, most US'ers seem to be willing to risk the destruction of all humanity because " 'We' can't let the dictator-of-the-day invade this country we don't care about and can probably not even place on a map!"