Neither the Archbishop nor the people he's defending seem to grasp that virtue rests on self-determination. There is no victory in a chastity enforced with necessity (see Aberlard, Peter!), and it is those who wrestle with the enemy, and throw him, who receive the laurels, not those who never enter the arena. This argument, by the way, is my chief complaint about socialism.
Moreover, how can one possibly say that the U.S. have lost the "power of self-criticism"? We have never been more self-examining than we are now. We take our dissenters, and instead of locking them up we give them radio shows. We worry more about enemy casualties than other countries worry about civilians.
I wasn't going to bother with this article, which is a school of sluggish fish in a tiny barrel, but then I came across this sentence: "'Violence is not to be undertaken by private persons'". I seem to have taken the opposite stance: I wonder if violence is only so to be undertaken. It is the private person who defends himself that leads to peace, and not all the police in the world can change that. I am the judge of my own interest, and the state would do well to remember that when the consequences of the social contract are worse than barbarism, that contract no longer stands. See The Ball and the Cross for some idea.
Law is just experience trying to get a word in edgewise about morality. Morality is a priori, although the specific instances of it may be occasioned by experience. I can't tell if Archbishop Williams agrees to this division, or if his statement that the recent war was "immoral and illegal" is something like the Prayer Book's "acknowledge and confess": a "doublet of synonyms".
UPDATE: Yes. We must have a right to defend ourselves that is independent of any artificial polis.