Military analyst Michael O'Hanlon shows how outside forces could successfully intervene to stop an ongoing cycle of warfare in a country whose government has collapsed or come under severe internal challenge. Based largely on recent U.S. experiences in Panama, Somalia, Bosnia, and elsewhere, as well as on U.S. military doctrine and information from the Pentagon's training and simulation centers, the book discusses the steps in an intervention and estimates likely casualties and costs. O'Hanlon shows that modern Western militaries are capable of executing these types of operations with high proficiency. While conditions are unlikely to resemble those of Desert Storm, which allowed the U.S. and allies to take full advantage of modern technology, top-notch militaries have advantages in infantry combat situations--night-vision equipment, attack and transport helicopters, counterartillery radars--that would enable them to establish order and prevail in any firefights. O'Hanlon warns that operations as casualty-free as those in Haiti and, to date, in Bosnia would be unlikely. Moreover, the political framework that outside powers would attempt to employ in establishing a new order would be critical: if intervening forces are seen as taking sides or occupying territory without legitimacy, they could meet protracted guerrilla-style resistance of the types witnessed in Vietnam, Afghanistan, and Somalia. Part of the Studies in Foreign Affairs series