If every single human were a pacifist, then pacifism would make sense. If every human were capable of being convinced of the wrongdoing of their actions, and more importantly, if they cared, then pacifism would still be a defensible position. But in the real world, there is such a thing as pure evil. There are such things as people who kill because they like it. If everyone who had the basic human ability to make moral decisions chose pacifism, then the ones who are left - the truly evil cases, the ones who are more like animals than humans, would simply kill until they got too physically tired, or bored, or ran out of victims. How can absolute refusal to defend the innocent against initiatory force be anything but an anti-life view? How can one claim to be in favor of innocent life if one would not end that which would destroy innocent life utterly if it had the power to do so?