In "What Does the Bible Say About Serving in the Military", you said that God would not condone or condemn the soldier. But, since the South lost the Civil War, could it be said that they sinned against God and that their loss was God's punishment for usurping the United States government?
A very astute question. It could be said that those who fought for the Confederacy were opposing God because they were opposing the government established by God. I'm not sure that the Bible would indicate that their loss was a punishment for opposing the United States government.
That raises several other related questions. By most accounts General Robert E. Lee was a more honorable and more admirable man than General George Washington. Both rebelled against the established government. By law (the Constitution of the United States as amended) the various states had a right to withdraw from the union, so the government for which General Lee fought had more of a legal right than the one for which General Washington fought. Yet the Americans won the Revolution and the Confederates lost the American Civil War. The only way, it seems, to ultimately know which government God wanted in place was by seeing which won. Can the soldiers below the highest levels be held accountable for fighting against a government that was later found to be established by God? I don't know, and the Bible is not clear on this.
I think the ultimate way of looking at this whole issue would be that a member of the military should obey lawful orders and not worry about the outcome. A Christian, though, should normally not be among those who are openly advocating rebellion against an established government. This, though, is my opinion, based on Romans 13:1-6.
"Let every soul be subject unto the higher powers. For there is no power but of God: the powers that be are ordained of God. Whosoever therefore resisteth the power, resisteth the ordinance of God: and they that resist shall receive to themselves damnation. For rulers are not a terror to good works, but to the evil. Wilt thou then not be afraid of the power? do that which is good, and thou shalt have praise of the same: For he is the minister of God to thee for good. But if thou do that which is evil, be afraid; for he beareth not the sword in vain: for he is the minister of God, a revenger to execute wrath upon him that doeth evil. Wherefore ye must needs be subject, not only for wrath, but also for conscience sake. For for this cause pay ye tribute also: for they are God's ministers, attending continually upon this very thing."