James Toner argues that the cardinal virtues are and must be the core values of the military. By embracing these values, the profession of arms serves as a moral compass in an increasingly confusing age. Building upon a bold introduction, which includes what many will regard as a surprising view of military ethics, Toner examines the four cardinal virtues -- wisdom, courage, temperance, and justice -- and places each in the context of a compelling case study from recent U.S. military history. He discusses the Flinn Case, the Lavelle Affair, a B-52 crash in Washington State, and the courageous actions of Hugh Thompson after My Lai. Morals Under the Gun connects ethics and moral theology with the armed services, demonstrating that the task of preserving virtue, both personal and professional, is a noble, if imperfectible, task.