Hundreds of thousands of white males died between 1861 - 1865 in the USA so that coloured folks would not be treated as property. Isn't that payment enough?
No. Emphatically no.
Your premise wrongly presupposes that black people owe the nation a debt for "rescuing" them from the very conditions that the nation itself imposed on them in the first place by kidnapping, enslaving, torturing, separating them from family, and killing them, and that the sacrifices of the Union soldiers in the Civil War were somehow wiping that debt clean. If an arsonist sets a house on fire and then pulls a family out of the burning house, he doesn't get to give out an exasperated "
You're welcome!" like he's owed something, and in fact he still owes the family a debt for setting their house on fire in the first place.
This also neglects the fact that hundreds of thousands of black freedmen and escaped slaves from the North and South also fought for their own freedom and the freedom of their compatriots, and others rebelled as they could while still in bondage.
Regardless of why Union soldiers chose to fight: whether it was because they were trying to preserve the Union, or because they staunchly opposed slavery, or both; or whether they were a volunteer or because they were drafted, is largely irrelevant. They still gave their lives for a noble cause and that should be honored. But it doesn't mean we can just say "We good?" to black people about all the stuff that came before that precipitated the war. One thing has nothing to do with the other and should never be considered the motive for doing the right thing.
Hundreds of thousands of American soldiers also died on the battlefields of Europe, Africa, Asia, and the Pacific in WW2, yet post-war we invested what in modern terms would be hundreds of billions of dollars in repairing the infrastructure of not only our allies but also our former enemies in Germany and Japan. If we can do that, why is there so much reluctance to also helping our own people who we wronged?
Some efforts were made to help black people after the Civil War during Reconstruction, but they were piecemeal, and rarely lived up to the promises made, and were accompanied by continued massive oppression that largely undermined their chances at recovery and improvement. We needed something along the scope of money invested in the Marshall Plan but directed towards helping former slaves move towards economic and social parity.
