The Western Confucian links to an essay by Dr. Robert Spaemann (wiki) on just wars. In the comments I write:

I suppose Professor Spaemann would have to further explain what he means by "territorial integrity." That a country's territory cannot be divided or taken over by another power? Or further, that its boundaries cannot be violated by being trespassed upon? Otherwise, I don't see how this is connected to the second part: "and others can declare war on them to pursue the problem at its root."

Some questions I have--
1. A nation-state that cannot police within its borders and therefore has lost control over its own territory is really not a nation-state. Therefore this should be recognized? or
2. A nation-state should continue to exist, but a new government should replace the inneffectual one. This can be facilitated by an outside agency, so long as the people consent?
3. But if it is impossible for an effective government to be created at the level of the nation-state, then the territory should be divided until governments that can be effective over a smaller area can be created?
4. If consent is not available, is it permissible for an outside agency to impose its own government? Some might say that that which has care of the international common good has the right to do so, and therefore the UN should be given this authority, but I am hesitant in conceding this.

Some more thoughts:

I would hold that any authority that has care of the 'international' common good must be shared by all peoples, whether it be directly or through their governments. If a people or their government withdraws, then there it no longer has any authority, and we return to what has been 'normal'--nations making and observing treaties and so on. "Legislative" power would require the cooperation of all nations, and "executive" power would be very limited, and as widely dispersed as possible. I haven't reasoned this out all the way--but I am inclined by this position for two reasons: (1) it would be a better check on tyranny, and (2) any other sort of arrangement would seem to be a dangerous act of human pride, an attempt to replace the kingship of Christ. Now in order to make the argument work, one can look first at the question of justice. And then show that even though other arrangements may be just, they may not be the best (or prudent).

I need a better understanding of authority, and how its determination and exercise relates to justice. If authority can be delegated, can it be recovered? Does delegation imply the surrender of all rights or powers? What rights or powers are retained?

Other writings by Dr. Spaemann:
Robert Spaemann. Rationality and Faith in God. Communio 32 2005
A Philosopher Reissues the Pope's Wager: To Live as if God Exists
Google Books: Happiness and Benevolence