"We know that no one ever seizes power with the intention of relinquishing it. Power is not a means; it is an end. One does not establish a dictatorship in order to safeguard a revolution; one makes the revolution in order to establish the dictatorship. The object of persecution is persecution. The object of torture is torture. The object of power is power."

Edit: Personally, it's this self-awareness of their own real motives that make the Inner Party of Ingsoc so scary.