Christians describe demons as dominated by the need to dominate. Domination is indeed evil.
Monarchs had the divine right of kings. But who's really in charge, the monarch, or God? There's an easy way to find out: do something God definitely doesn't want done. If it works, the king really is the dominant one. They'll get a nice high and want another hit, so they'll do something God would dislike even more.
Presidents, prime ministers, and chancellors represent the will of the people and govern with their consent. Unless they're really in charge, in which case they can do something against the will of the people and survive. The most dominant can directly contradict the people's will repeatedly and emerge unscathed. Thus, they do precisely this.