Facepalm

I mean, it kind of wasn't...

Lincoln honestly wouldn't stop talking about how he wasn't gonna touch slavery.

It is found in nearly all the published speeches of him who now addresses you. I do but quote from one of those speeches when I declare that "I have no purpose, directly or indirectly, to interfere with the institution of slavery in the States where it exists. I beheve I have no lawful right to do so, and I have no inclination to do so." Those who nominated and elected me did so with full knowledge that I had made this and many similar declarations, and had never recanted them. And, more than this, they placed in the platform for my acceptance, and as a law to themselves and to me, the clear and emphatic resolution which I now read:

Resolved, That the maintenance inviolate of the rights of the States, and especially the right of each State to order and control its own domestic institutions according to its own judgment exclusively, is essential to that balance of power on which the perfection and endurance of our political fabric depend, and we denounce the lawless invasion by armed force of the soil of any State or Territory, no matter under what pretext, as among the gravest of crimes.

https://millercenter.org/the-presidency/presidential-speeches/march-4-1861-first-inaugural-address

What started it was the south thought the feds should be able to enforce southern law (escaped slaves are still slaves, and northern states had to return them) and the Feds said they couldn't force one state to follow another state's laws.

It's a valid distinction, but almost certainly not what she told her kids.

Like when people say it was over "states rights" but ignore the Feds sided with state's rights, and the South was the one arguing for a stronger federal government.

However during the war, Lincoln did outlaw slavery, but that was more of an economic sanction to dissuade European governments funding the South by buying up resources and land. The South would have still lost but it would have taken far longer if they were selling land/plantations/slaves to wealthy foreigners

It's one of the few things pretty much everyone gets wrong when you ask what causes it.