NATO’s military campaign against Yugoslavia last year was illegal but legitimate. This was a generally (but not unanimously) agreed upon conclusion at a recent conference on the “Implications of the Kosovo Conflict on International Law,” sponsored by the Institute for International Policy Studies in Tokyo. It was illegal because it did not have United Nations Security Council authorization. It was deemed to be legitimate, nonetheless, since UN approval was not a realistic option, thereby leaving NATO with only two choices (diplomacy and sanctions having already failed): do nothing in the face of blatant crimes against humanity, or intervene militarily. Of these two “evils,” intervention was the lesser sin.