But in a fundamental sense, Trump’s most disturbing remark over the past few days may have been his unprompted comment about Abraham Lincoln during an appearance on Fox News: “Lincoln was probably a great president. Although I’ve always said, why wasn’t that settled, you know? I’m a guy that — it doesn’t make sense we had a civil war.”

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And if he is, here’s the thing: The Civil War couldn’t have been “settled” by moderating Northern demands that the South give up its slaves, because there was no such demand.

Yes, Northern states had banned slavery within their own borders and many Northerners considered slavery abhorrent. But outspoken abolitionists who sought to end slavery everywhere were a small minority. If the South hadn’t seceded, slavery might well have continued unimpeded for decades.