You’re making up something that YOU think “makes sense” but you know nothing of historic reality.
“Those at the top” included powerful republican senators who demanded an end to slavery as their biblical duty.
Further, the South started the war by seceding, it was not in the hands of “Northern industrialists”.
You need to learn things, not sit around in a bull session making up what “must have been true”. It wasn’t.
Lincoln was, indeed, a white supremacist. In his 1858 debate with Sen. Steven Douglas, Lincoln maintained, And inasmuch as they cannot so live, while they do remain together there must be the position of superior and inferior, and I as much as any other man am in favor of having the superior position assigned to the white race.