Professor Nagl�s War: "The paradox might be impossible to resolve. The United States military has done a good job, in general, of limiting what it refers to as ''collateral damage'' in its occupation of Iraq. Yet for every raid that finds its target, there seem to be nine that don't, and in those nine, soldiers often point weapons at civilians, drive through fields and backyards, break down doors and detain people who are later released. This is the inherent messiness and slowness of counterinsurgency that T.E. Lawrence wrote of, and it is a key reason that the failure rate in counterinsurgency is so high"

Yet if predicting the future is a hopeless endeavor, learning from the past is not. The counterinsurgency books that Nagl studied do impart an important lesson. The goal the United States hopes to reach in Iraq -- a successful counterinsurgency that does not drag on for years and does not involve a large amount of killing -- has never been achieved by any army.




Peter Maass, a contributing writer, is the author of ''Love Thy Neighbor: A Story of War.'' He has reported extensively for the magazine from Iraq.