Voilent Politics

I've just finished Violent Politics: A History of Insurgency, Terrorism, and Guerrilla War, from the American Revolution to Iraq by William R. Polk.

Highly recommended. Informative and well written.

Polk examines insurgencies from revolutionary America to Afghanistan, discussing why they started, why they were successful or failed, and the strategies of the insurgents and their opponents.

A major point is that if the causes of the insurgency remain (rule by an outside group), the insurgency will remain until victory, even if there are pauses. Thus for the invader there is no victory in the long run.