In these days, the authorities claim the right to control not only the policy of the nation but also the actions of every individual within it; and their claim has the support of a large section of the people of the country, and of a peculiar force of emotion. This support is gained, and this emotion caused by the fact that they are “evil things” that we are fighting against. That they are evil we need have no doubt; yet many of us still feel distrust of these claims and these emotions lest they blind men to their duty of considering carefully, before they act, the justice of the things they propose to do. Men can be moved to fight by being made to hate the deeds of their enemies; but a war is not made just by the fact that one’s enemies’ deeds are hateful. Therefore it is our duty to resist passion and to consider carefully whether all the conditions of a just war are satisfied in this present war, lest we sin against the natural law by participating in it.
For men to choose to kill the innocent as a means to their ends is always murder.
It is nonsense to pretend that you do not intend to do what is the means you take to your chosen end. Otherwise there is absolutely no substance to the Pauline teaching that we may not do evil that good may come.