Why do empires build walls and fences? Are they for defensive purposes only, to keep the 'barbarians' at the gate; or do they also function as complex offensive military structures to subjugate and control the colonised? In Empires and Walls, Mohammad A. Chaichian meticulously examines the rise and fall of the walls that are no longer around; as well as the impending fate of 'neo-liberal' barriers that imperial and colonial powers have erected in the new Millennium. Chaichian provides evidence that walls always signal the fading power of an empire.