Over the last decade (and indeed ever since the Cold War), the rise of insurgents and non-state actors in war, and their readiness to use terror and other irregular methods of fighting, have led commentators to speak of 'new wars'. They have assumed that the 'old wars' were waged solely between states, and were accordingly fought between comparable and 'symmetrical' armed forces. Much of this commentary has lacked context or sophistication. It has...