A Flowchart on the Morality of War
Are moral considerations applicable to war?
No. This is positivistic political realism. "[M]orality has no application whatever to international relations" (page 56).
Yes. Should moral considerations be applied to war?
No. This is strong normative political realism. "[Moral] notions should [not] be appealed to in international relations" (57).
Yes. Should moral considerations be decisive?
No. This is weak normative political realism. "[M]oral considerations should [not] be decisive in the determination of [foreign] policy" (57).
Yes. This is idealism. "[S]tates ought always to act morally" (57). Is war ever morally justified?
No. I call this extreme pacifism.
Yes. Is war morally justified today, given the technology that exists?
No. I call this moderate pacifism. "[W]ar in the modern world is not morally justified" (14). Holmes is in this category.
Yes, provided certain requirements are satisfied. The just-war theory falls in this category. "[W]ar is sometimes morally permissible" (49).
This flowchart is based on Robert L. Holmes, On War and Morality (Princeton: Princeton University Press, 1989).