In his inaugural address, he actually proposed amending the constitution to make slavery unrepealable. Its cus the north was coming up with all these lucrative tarrifs to be born by the south, which was pissing them all off, so it was an attempt to try and get them to stay in the union.
But as far as ending slavery… there’s a really easy and peaceful way to do it. You probably learned about how northers were forced to return escaped slaves to the south. This is actually a huge deal. Its how slavery in Brazil was destroyed. They eventually outlawed slavery (probably to save face), but slavery was becoming increasingly unprofitable since slaves could just escape to Ceara, where slavery was illegal.
I.e. the cost of slavery increases when you have to monitor them 24/7.