What does a Warlord do?

In West Africa Always Wins:

...most of what Ryszard Kapuscinski wrote about the warlord phenomenon still applies to the handful of ex-students and poorly educated former army sergeants who have been plundering the northern half of Ivory Coast for the past seven years. "Warlords," he writes in The Shadow of the Sun, "are the sowers of tribal and racial hatred in Africa. They will never admit to this. They will always proclaim they are leading a national movement or party...What does a warlord do? Theoretically, he fights with other warlords. Most frequently, however, he is busy robbing his own country’s unarmed population. The warlord is the opposite of Robin Hood. He takes from the poor to enrich himself and feed his gangs. We are in a world in which misery condemns some to death and transforms others into monsters. The former are the victims, the latter are the executioners. There is no one else.”