Principles that are mistakenly high and strict are a trap; they may easily lead in the end directly or indirectly to the justification of monstrous things. Thus if the evangelical counsel about poverty were turned into a precept forbidding property owning, people would pay lip service to it as the ideal, while in practice they went in for swindling. “Absolute honesty!” it would be said: “I can respect that – but of course that means having no property; and while I respect those who follow that course, I have to compromise with the sordid world myself.” If then one must “compromise with evil” by owning property and engaging in trade then the amount of swindling one does will depend on convenience. This imaginary case is paralleled by what is so commonly said: absolute pacifism is an ideal; unable to follow that, and committed to “compromise with evil,” one must go whole hog and wage war a outrance….
[P]acifism teaches people to make no distinction between the shedding of innocent blood and the shedding of any human blood. And in this way pacifism has corrupted enormous numbers of people who will not act according to its tenets. They become convinced that a number of things are wicked which are not; hence, seeing no way of avoiding “wickedness,” they set no limits to it. How endlessly pacifists argue that all war must be a outrance! that those who wage war must go as far as technological advance permits in the destruction of the enemy’s people. As if the Napoleonic wars were perforce fuller of massacres than the French war of Henry V of England. It is not true: the reverse took place… Pacifism and the respect for pacifism is not the only thing that has led to a universal forgetfulness of the law against killing the innocent; but it has had a great share in it.
-G.E.M. Anscombe, War and Murder.