The Syrian Civil War that began in 2011 killed more than 400,000 civilians. Could a limited intervention motivated by humanitarian concerns have reduced the death toll at an acceptable cost to the intervenors? I distinguish between two approaches to intervention: penalizing atrocities, by raising the cost and lowering the benefit of killing civilians; and fostering a balance of power, to convince the two sides that they cannot win on the battlefield and so must negotiate an end to the war. I show, using a game-theoretic model, that fostering a balance of power causes the government to commit more atrocities and prolongs the war. Penalizing atrocities, while it increases the likelihood of war, can reduce the expected level of atrocities. The model helps account for the failure of US efforts to promote negotiations by aiding Syrian rebels, and the success of efforts to deter Syrian chemical weapons use through threats and limited strikes.

始于 2011 年的叙利亚内战导致超过 40 万平民丧生。出于人道主义考虑而进行的有限干预能否以干预者可接受的成本减少死亡人数？我区分了两种干预方法：通过提高成本和降低杀害平民的利益来惩罚暴行；并促进权力平衡，说服双方他们无法在战场上获胜，因此必须通过谈判结束战争。我使用博弈论模型表明，促进权力平衡会导致政府犯下更多暴行并延长战争。惩罚暴行虽然增加了战争的可能性，但可以降低暴行的预期程度。该模型有助于解释美国通过帮助叙利亚叛军促进谈判的努力失败，以及通过威胁和有限打击来阻止叙利亚使用化学武器的努力的成功。