History Memes

The preservation of the Union was powerful for several reasons:

1. This was at the height of 19th century nationalism - the sense of the 'nation' as a singular 'tribe' was an emotive call. To hear that others would turn against your 'tribe' and take what it, and your family, had spent generations building, was a very deep and real offense. There is a sense that this 'national project' falling apart entirely would render meaningless generations of work and idealism and sacrifice.

2. There was a serious suspicion that allowing secession would mean the complete dissolution of the Union. I don't remember if it was Grant or Sherman who said it, but one of those two generals noted that allowing secession would ultimately reap the reward of total national chaos, a la Mexico (which had been having civil wars and insurrections like they were going out of style).

3. The fact that secessions was quite explicitly due to the fact that a democratic election didn't go the Southerners' way was deeply offensive to democratic and republican norms of Americans at the time; and the fact that many secession votes were held under armed guard by secessionist militias was, furthermore, an additional offense that gave a very real sense that the plantation class was dragooning the South into a war for the plantation class's interests. Not coincidentally, this was largely the view of Southern Appalachia, where slaver power was weak, and Unionist guerillas were widespread.

Also, I'd like to note that a great many volunteers for the Union were ardent abolitionists even at the start, and that abolitionist sentiment actually became significantly stronger as the war wore on. There's a really great letter from an enlisted Maine boy at the start of the war I like to bring up:

What a splendid cause is this on which we are engaged. I think it is the grandest that ever enlisted the sympathies of man. Nobler even than the Revolution for they fought for their freedom while we fight for that of another race. I firmly believe that the doom of slavery is fixed and if it is not wholly rooted out by the present war, measures will be taken to wipe it out forever. If such an event can be consummated by any sacrifice of mine, it shall be cheerfully made. I could die for this as readily as I could lie down to rest at the close of a day of wearisome toil. Men have called this age dull. They can do so no more ... War is bad, heaven knows, but slavery is far worse. If the doom of slavery is not sealed by the war, I shall curse the day I entered the Army, or lifted a finger in the preservation of the Union. Of the old Union we have had enough and more than enough.