Suppose for a moment that the American Revolution was an unjust war. [Since]... Americans fought it anyway and won it, what does that say about the legitimacy of America’s sovereignty in the eyes of God?In addition to the stipulations of just war (which are not exclusively Christian), we should also reflect on this question in light of the biblical prohibition against taking up arms against legitimate government.
Almost all nations have skeletons in their closets. If the practice of unjust wars invalidates a nation's sovereignty, then all nations have lost their sovereignty, except maybe Iceland. When Paul wrote Romans 13:1-7, he was referring to the Roman Empire, much of which had been founded on wars of aggression. However, this did not invalidate Rome's authority, according to Paul - he argued that we should submit to existing authorities. And of course, America has had other wars that are of much greater concern. The Indian Wars, the Mexican-American War, and the Spanish-American War were far more unjust than the Revolutionary War. If we use the 1-100 "just war scale" I mentioned in the first post, then I give the Revolutionary War about 60 or 70, the Indian Wars about 10, and the Mexican and Spanish Wars about 20 or 30.
If you have the (mistaken, in my mind) belief that America was somehow founded by God as a chosen nation, then analyzing the Revolutionary War by just war or biblical criteria will certainly shake that belief.
We need to avoid what philosophers call the genetic fallacy - the false idea that origins determine everything. If, as some Christians claim, America was properly and justly founded as a Christian nation, that does not say anything - positive or negative - about the country's later actions. If, as I am suggesting, the founding war of America was less than fully just and biblically questionable, then that also says little about the later actions of the country. America has demonstrated that it is capable of both just and unjust wars, regardless of the status of its founding war.
Maybe I am biased as an American, but I think that America has been more just in many of its wars (in both causes and in practices) than many other nations. The Indian Wars seem to be the most notable exception (we haven't talked about Iraq yet - that will be the next and hopefully last just war post).