Compassion is not a popular virtue. Very often when I talk to religious people and mention how important it is that compassion is the key that it's the sine-qua-non of religion people look kind of balked and stubborn sometimes as much to say what's the point of having religion if you can't disapprove of other people?
When the tyrant has disposed of foreign enemies by conquest or treaty and there is nothing more to fear from them then he is always stirring up some war or other in order that the people may require a leader.