When civil wars break out, there is frequently debate about whether and how outside countries should get involved. Opponents of intervention frequently bring up the potential that the conflict will become a “quagmire,” often with reference to cases such as the United States’ involvement in Vietnam or the Soviet and U.S. military interventions in Afghanistan. Despite the frequency with which the potential for “quagmire” is discussed in policymaking circles, there is almost no scholarly work analyzing this concept. In Quagmire in Civil War, Jonah Schulhofer-Wohl seeks to fill that gap by examining what quagmire is and why some civil wars do, and do not, become quagmires.

Schulhofer-Wohl defines a quagmire as occurring when “for at least one of the belligerents, continuing to fight costs more than the expected benefits; but withdrawing will increase rather than avert those net costs” (p. 4). The central argument is that quagmire is made, not found, and that it results from decisions both by the domestic belligerents and by their international backers. External support to belligerents enables them to continue fighting when they otherwise would not be able to do so (or would see compromise as preferable). However, this external support is not