Given the extremely high cost of overseas military operations today, the author offers readers scholarly insights as to what motivates kingdoms, countries, and groups to engage in religious conflict, beginning with those found in the Hebrew Bible. To do this, he analyzes three related religions, Judaism, Christianity, and Islam, to determine their similarities and differences regarding the killing of people. The areas of conflict analysis include Fundamentalism, Proselytization, Sacrifice (to include martyrdom), and Revenge (to include genocide). The insights of preeminent religious and political scholars are integrated into this comprehensive analysis of conflict involving religion, leading to an answer to the ultimate question: Is the killing worth it?