The North -- aka the United States of America -- didn't "invade" the South. Rebels in a Southern State fired on and then seized the property of the United States of America, which started a war. This after stealing from the Federal treasury and wringing one concession after another in bad faith negotiations for eight decades.
The United States of America didn't "hold on" to any slaves. Contrary to the idiotic statement in your post, Lincoln was a Constitutionalist, who did not believe either he, or Congress, had the authority to free slaves. You will note if you ever bestir yourself to read some history beyond the lame nonsense written by Southern (Gone With the Wind, Birth of a Nation) "historians," that the Emancipation Proclamation only freed those slaves in territories which had declared themselves outside of the Constitution. Emancipation was not necessary in most of the Northern US, but because the Constitution remained, so did slavery in the border States. North of the MD line, Americans did not own slaves.
Nobody claimed the Americans were "pure as the wind-driven snow." But what history shows was that 1) The Republican Party was founded to abolish slavery 2) When a Republican President was elected, the slave States decided to secede 3) When the Civil War ended, the Constitution was amended freeing 1/8 of the US population from Slavery 4) That Constitution was amended by, and the blood was shed to do that by white, male, Americans.
You can pretend these facts don't exist. But facts are stubborn things.
Nobody seceded over the tariff, nor over any "States Rights" issue. The claim of "States Rights" is easily enough silenced by a simple question: over what "right" did the slave States secede? [Hint: What Ayn Rand correctly described as a "right" that no state possesses: the right to buy, sell, and own other human beings.]
There's no more "racism" in these facts than the legitimate criticism of 0bama. But I'm not surprised to find you in bed with the Commies in that regard. Politics makes for strange bedfellows, and the multi-culties have always been in bed with the slave-masters in maintaining the preposterous fantasy that AmeriKKKa is far too racist to ever have abolished black slavery. The truth is that, as Thomas Sowell pointed out at some length in Race And Culture, [Paraphrasing] "The fact that Americans owned slaves is not remarkable. Slavery has existed (and continues to exist) throughout human history. What is remarkable about the Anglo-American civilization is that it abolished slavery."
Go and actually read the contemporary news editorials written in Southern papers during the Antebellum and Civil War. If you're honest with yourself, you'll very quickly disabuse your mind of the lie that the Civil War was fought over anything but slavery.
YOU said the North fought the war to free the slaves, so by inference you are claiming the North invaded the South. I know that’s not right, but if you’re going to keep repeating the lie then you have to also accept the inferences that you are making.