"With this in mind, we set out to mine the history of recent, similar internecine conflicts for lessons that might help the United States to devise a set of strategies to deal with the looming prospect of a full-scale Iraqi civil war. We scrutinized the history of civil wars in Lebanon in the 1970s and 1980s; Afghanistan, Bosnia, Chechnya, Croatia, Georgia, Kosovo, Macedona, the Nagorno-Karabakh conflict, and Tajikistan during the 1990s; as well as the conflicts in Congo and Somalia that rage to this day (we present eight of these cases in five appendices to the paper to provide additional historical insight for readers wishing to delve deeper into this question themselves). From these wars we distilled a set of lessons regarding how civil wars can affect the interests of other countries, even distant ones like the United States, and then used those lessons to fashion a set of recommendations for how Washington might begin to develop a new strategy for an Iraq caught up in all-out civil war ... Our conclusions are not encouraging. We found that much of what is considered "conventional wisdom" among Westerners about how to handle civil wars is probably mistaken. For instance, we found little to support the idea that the United States could easily walk away from an Iraqi civil war--that we could tell the Iraqis that we tried, that they failed and that we were leaving then to their fates. We found that "spillover" is common in massive civil wars; that while its intensity can vary considerably, at its worst it can have truly catastrophic effects; and that Iraq has all the earmarks of creating quite severe spillover problems. By the same token, we also found that the commonly held belief that the best way to handle a civil war is to back one side to help it win was equally mistaken. We found few cases of an outside country successfully helping one side or another to victory, and the outside power usually suffered heavy costs in the process"--Preface, page ix.