Properly read in its historical context, the text does not refute JasonC whatsoever. You see, the South didn’t care what he said as President, they already knew how he felt about slavery, and what he would ultimately do. Which, btw, he did. The emancipation declaration against the slave-holding states at war with the union was, thus, something of a Southern-induced self-fulfilling prophecy.
So on top of being a butcher he is a liar too. Some defender you are....
Then you ought to tell JasonC that. He wrote something different ..... failure of Lincoln to support Dred Scott.
The South seceded because of the worsening sectional political and economic warfare and the remorseless Yankee propaganda war against the South, which foreshadowed what the Yankees intended to do as much or more than anything Lincoln said.
After the John Brown Raid, "we're sorry you didn't all get killed in your beds" kind of said it all. That was the really fatal moment -- and ironically, Lincoln got that one right: he publicly demurred from the lugubrious Northern display for Brown. But what John Brown did -- and especially the ruthlessness and bloodshed -- was fully encompassed by Lincoln's ultimate intentions.