In Lord of the Flies, what makes Jack powerful?

Many things make Jack powerful. First is that he is hungry for power. Second in that he is physically big. But ultimately Jack is powerful because he is prepared to use the wild power of the uncivilised tyrant.

Jack is Saddam Hussein gassing the Kurdish villages that may contain rebels. He is Stalin starving millions of Ukrainians as a warning to others. He is Pol Pot killing the middle class Cambodians because they are a threat to his rule.

Jack is powerful because he doesn't care about 'the rules' of society and is determined to be absolute ruler, at any cost.