Walzer, Michael

Walzer, Michael. Just and Unjust Wars A Moral Argument with Historical Illustrations, 3rd edition (New York Basic Books, 2000). 

Allen Buchanan argues persuasively for the need for a moral theory of international law in Justice, Legitimacy, and Self-Determination Moral Foundations for International Law (Oxford Oxford University Press, 2004). Michael Walzer engages in a deeply moral discussion of conventions of war in Just and Unjust Wars A Moral Argument with Historical Illustrations, 3rd ed. (New York Basic, 2000). For a good discussion of the need for normative theorizing, see Allen Buchanan and David Golove, Philosopy of International Law, in The Oxford Handbook of Jurisprudence and Philosophy of Law, ed. J. Coleman and S. Shapiro (Oxford Oxford University Press, 2003), pp. 868-934. 

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