http://predragrajsic.blogspot.com/2009/08/humanitarian-war-fallacy.html

„He who joyfully marches to music in rank and file has already earned my contempt. He has been given a large brain by mistake, since for him the spinal cord would fully suffice. This disgrace to civilization should be done away with at once. Heroism at command, senseless brutality, deplorable love-of-country stance, how violently I hate all this, how despicable an ignorable war is; I would rather be torn to shreds than be a part of so base an action! It is my conviction that killing under the cloak of war is nothing but an act of murder.” -- Albert Einstein

Even though it is usually portrayed as a human rights doctrine, the idea of a humanitarian war seems to be based on the utilitarian theory of rights, which states that an action is justly taken if the gains from the action exceed the losses. I think there are at least two fundamental problems with applying this principle for justification of a humanitarian war: (1) utility (satisfaction of the decision maker) is never a function of one variable; (2) decision on taking the action is made ex ante (before the action), while the evaluation whether it was justified can only be done ex post (after the action).

(1) In a humanitarian war, gains would be represented by atrocities prevented by the war, and losses would be represented by the atrocities resulting from the war. However, in the theory of choice, gains and losses refer to gains and losses in utility - satisfaction of the decision-maker. The problem here is an underlying assumption that that the agent waging a humanitarian war, derives utility only from preventing atrocities (and equivalently, from minimizing atrocities resulting from a humanitarian war). This could well be true if the agent waging a humanitarian war is the omnipotent, ever-loving, perfectly ethical God, but we know this is not the case. Actually, some people know this is not the case but there seems to be many who would like to believe otherwise.

(2) In order to determine whether a war was indeed humanitarian, there needs to be an accounting evaluation after the war. Assuming there exists a unit of measure for atrocities, one would measure the atrocities committed as a result of a humanitarian war and compare them to the atrocities that were prevented by the war. The problem here is that we will never know what exactly a humanitarian prevented. Thus, there is nothing concrete that can be compared to the outcome of such a war. Assuming we are willing to accept ethical categorisations based on speculation, this problem could, however, be overcome to some extent by comparing the outcome of a humanitarian war to the atrocities committed before it started and assume that the trend would not have changed in the absence of a humanitarian intervention. However, I doubt any of the „humanitarian” interventions up to date would be justified using this evaluation tool.