I do agree the North was in no danger of being invade/occupied by the South. Even Southerners knew that was an impossibility from day one.
But it was about slavery as many Southerners stated...
"What did we go to war for, if not to protect our [slave] property?" - CSA senator from Virgina, Robert Hunter, 1865
"The South had always been solid for slavery and when the quarrel about it resulted in a conflict of arms, those who had approved the policy of disunion took the pro-slavery side. It was perfectly logical to fight for slavery, if it was right to own slaves." - John S. Mosby
"What was the reason that induced Georgia to take the step of secession? This reason may be summed up in one single proposition. It was a conviction, a deep conviction on the part of Georgia, that a separation from the North-was the only thing that could prevent the abolition of her slavery." -- Speech of Henry Benning to the Virginia Convention
... and the average Southerner owned no slaves.
They still apparently had a dog in the fight.
"The vandals of the North . . . are determined to destroy slavery . . . We must all fight, and I choose to fight for southern rights and southern liberty." - Lunsford Yandell, Jr. to Sally Yandell, April 22, 1861
"Better, far better! endure all the horrors of civil war than to see the dusky sons of Ham leading the fair daughters of the South to the altar." - William M. Thomson to Warner A. Thomson, Feb. 2, 1861
"A captain in the 8th Alabama also vowed 'to fight forever, rather than submit to freeing negroes among us. . . . [We are fighting for] rights and property bequeathed to us by our ancestors.' " - Elias Davis to Mrs. R. L. Lathan, Dec. 10, 1863
"Even though he was tired of the war, wrote a Louisiana artilleryman in 1862, ' I never want to see the day when a negro is put on an equality with a white person. There is too many free [n-word]s. . . now to suit me, let alone having four millions.' " - George Hamill Diary, March, 1862
"A private in the 38th North Carolina, a yeoman farmer, vowed to show the Yankees ' that a white man is better than a n****r." - Jonas Bradshaw to Nancy Bradshaw, April 29, 1862
"A farmer from the Shenandoah Valley informed his fiancée that he fought to assure 'a free white man's government instead of living under a black republican government.' " - John G. Keyton to Mary Hilbert, Nov. 30, 1861
"The son of another North Carolina dirt farmer said he would never stop fighting the Yankees, who were 'trying to force us to live as the colored race.' " - Samuel Walsh to Louisa Proffitt, April 11, 1864
"Some of the boys asked them what they were fighting for, and they answered, 'You Yanks want us to marry our daughters to the n****rs.' " - Chauncey Cook to parents, May 10, 1864
"An Arkansas captain was enraged by the idea that if the Yankees won, his 'sister, wife, and mother are to be given up to the embraces of their present dusky male servitors.' " - Thomas Key, diary entry April 10, 1864
"Another Arkansas soldier, a planter, wrote his wife that Lincoln not only wanted to free the slaves but also 'declares them entitled to all the rights and privileges as American citizens. So imagine your sweet little girls in the school room with a black wooly headed negro and have to treat them as their equal.' " - William Wakefield Garner to Henrietta Garner, Jan 2, 1864
"[If Atlanta and Richmond fell] we are irrevocably lost and not only will the negroes be free but . . . we will all be on a common level. . . . The negro who now waits on you will then be as free as you are & as insolent as she is ignorant.' " - Allen D. Chandler to wife, July 7, 1864
So your your "theory' is well...BS.
A lot of that goes on in these Civil War threads.
“Except the war wasn’t about slavery as Lincoln stated and the average Southerner owned no slaves. So your your “theory’ is well...BS.”
Wars are started and supported by politicians and moneyed interests, both of which were the ruling class of the South.
Much like our Middle East oil wars it wasn’t the common soldier who decided to start the war.
You are right the U.S. did not go to war over slavery. They were attacked by rebels who attempted to break apart a perpetual union over the results of a constitutionally mandated election. Why did they rebel? Because they feared that the newly elected republicans would stop the spread of slavery and eventually try to end it. Later the U.S. adopted freedom for the enslaved as a war aim.
As far as Lincoln being a racist? Almost everyone was during that time compared to now. However, Lincoln, from an early age, detested slavery and wanted to see all men be free. Which you would know if you did any research on Lincoln. This put Lincoln, morally, head and shoulders above every leader in the pretend confederacy.