But can there be a “just war”? Presumably you would agree that a nation of libertarians has the right to defend itself from attack, and that such a defense would necessarily require that the libertarian citizens of that nation must sacrifice some of their personal autonomy to mount an effective defense. Assuming you agree that a libertarian nation may (and should) defend itself from an aggressor, then would you agree that a libertarian nation should go to the aid of another libertarian nation that has been attacked? Or to the aid of a democratic nation that is not fully libertarian, but is friendly to our libertarian nation?
If I see an aggressor attacking my innocent neighbour, do I not have some obligation to help that neighbour, whether by direct action or requesting the assistance of some authority? If I see a group of bad people oppressing the citizens of another country and denying them their rights to life, liberty, and property, should I simply avert my eyes?
I consider myself to be libertarian, and I have difficulty understanding how a libertarian can be 100% anti-war. I think a libertarian must be willing to fight for libertarian ideals, and aid others in achieving those ideals, or we will simply be picked off one by one.