I'm aware, but given that a predominantly Republican Supreme Court declared in that era that the 14th amendment somehow didn't give the government any power to protect Black rights, maybe it would be necessary to explicitly grant Congress the power to draw the districts. Maybe even, as in other countries, declare that Representatives serve the nation and not their own districts, but that would be taking it too far, maybe.
Now, I'm going to give a very late reply to some interesting posts made before the update...
It's sad, but prejudice is a learned behavior. A lot of the most fiery racists and Lost Causers were people who hadn't been born when the Civil War took place or were too young to remember it. A lot of the terrorists who attacked Black people in the 1876 elections were "young bloods", from teenagers to young adults who were just toddlers during the war.
Many people may not realize that Lee's Army was quite literally melting away in the road to Appomattox. He only surrendered because the alternative was destruction at Grant's hands - or taking to the mountains as bandits.
We've reached a point where some officers and officials simply won't be given the option to surrender, because the US will demand they stand trial for war crimes. Others might be given the chance to surrender, but the cartels certainly won't include complete immunity for all officers - but most likely for the common soldiers only. Those with a shred of honor will probably choice to surrender themselves in exchange of protection for their men.
The Union is aware of this. Though many Northerners are still wary of keeping up with what's basically become a class war by now, in rhetoric and action they advocate for the destruction of the planter class as something that will benefit the poor Whites. That's why they offer pardons, land and Bureau aid to those who desert the Confederacy. The only ones likely to keep fighting are the die-hards that it would be better to get rid of anyway.
That's the other factor, by the end the destruction would be so complete that the guerrillas simply wouldn't have any people to give them the necessary food and supplies. Confederate civilians already hide their food from their own soldiers, it's unlikely they will give up what little they have to an insurgency that's doomed to failure after they've seen their great armies ground to dust and destroyed. And if the guerrillas simply rob the civilians... well, that's not good for their long term prospects, certainly.
By the way, the Union is already punishing whole towns for guerrilla activities. In the Kansas-Missouri border and along the Mississippi, Union commanders often expel civilians, sack and confiscate plantations, and hold people hostage to try and control guerrilla activity. Though it's not generalized, often captured guerrillas are executed in revenge for raids and massacres - unless the guilty turn themselves in first. And, of course, cities that refuse to surrender are often completely destroyed. Conversely, the Confederates too victimize whole communities, even resorting to torturing women and children to draw their Unionist husbands out from the swamps and woods.
The two main factors that I hope will limit the vindictiveness of Reconstruction and the Union occupation is: 1. The Yankees see this as merely reclaiming their land and restoring the Union. They don't see themselves as beating a foe, like the Soviets did when they faced Germany. So they won't want to exterminate all Southerners, only the rebels, giving a chance to all the rest to surrender. Naturally, some abuses will still happen. 2. Radicalism is characterized by utopian idealism, not vindictive revenge. I can't find many Radicals openly calling for complete devastation for the sake of devastation. In fact, most of the bloody appeals came from people who were not really Radicals, such as Andrew Johnson.
One of my favorite movies! However, note that we've already reached the untempered version of Reconstruction as described by Lincoln - we have "land appropriation" in the form of extensive land redistribution, we have "revolutionary tribunals" in the form of military and Bureau courts that regularly trial traitors both North and South, we have "punitive measures" in the form of bills to confiscate property and punish rebellion.
I mean, again, we've reached that point. The Union has already established what are basically concentration camps in areas affected by guerrilla warfare, as the secesh civilians found to have been helping civilians are often expelled and driven to camps where they won't be able to aid the outlaws and are basically held hostage to prevent massacres. It's not as bad as the British camps, since most of the time the Union is actually just heavily occupying a town to prevent it from helping civilians, but in extreme cases they may be torched and the civilians are expelled without any aid - which has, you can imagine, resulted in atrocious casualties. Some civilians left voluntarily, which has only worsened the refugee crisis and set the conditions for the imminent famine. As far as scorched earth tactics, Grant and Sherman have already thoroughly devastated the Mississippi Valley and large areas of Louisiana to deal with guerrillas. The difference with the British is, of course, that after imparting so much destruction the Yankee soldiers always set down and offer land, food, supplies and pardons to those who want them. So a man may see his land sacked and food eaten... but the next week the Yankees would be giving him better land and better tools, and feeding and protecting him until the first crop is ready. At the very least this should show him that keeping up the fight won't achieve anything - even if resentment continues. At the end of the day, we'll have to do with passive loyalty bred from self-interest when genuine loyalty bred from love of the Union is not possible.
Indeed, but my goal is a better US and turning the South into Ireland won't do the trick.
There will be outlaws for many years after the war. As for the battle, I am envisioning a magnificent last stand. Keep reading, we're approaching the end!
The Native Americans sadly will probably not be part of the body politic anytime soon. But aside from that, the coalitions are really spot on. Still, at some point there probably won't be another realignment because it would be hard for a party to champion both the cause of the freedmen and of the robber barons.
Already picturing the scene of Lincoln finally returning the capital to Washington as the final sign that the war is truly over (though its problems continue).
Unfortunately, not many Radicals seemed interested in the plight of Native Americans. Most subscribed to the idea that it was the destiny of the US to extend from sea to shinning sea, and the better ones envisioned a "fair deal" for Native Americans that was benign paternalism and eventual assimilation. They would be most likely to argue that Black people have as much as White people the right to rob Natives of their lands.
I think I did use that quote somewhere, in fact, but I have indeed adopted your idea that Lincoln, based on the more radical war, has made attempts to prevent "distractions" in the form of wars with Native American tribes. So yeah, I think it's canon that the food got there in time and conflict was mostly avoided.
That, incidentally, means that the largest mass execution in American history is instead the execution of 82 soldiers of Forrest's command for the Fort Pillow massacre and other war crimes.
