Appearing as a guest on Friday's Real Time with Bill Maher on HBO, longtime NBC presidential historian Doris Kearns Goodwin cracked that maybe the U.S. should have let the South go as she and host Maher fretted over U.S. Supreme Court nominee Brett Kavanaugh's popularity in red states.

She even invoked the infamous caning of abolitionist Massachusetts Senator Charles Sumner in 1856 that made South Carolina Congressman Preston Brooks popular in slave states and foreshadowed the Civil War.

After host Maher asked if the partisan fight over the Supreme Court was a "low" in U.S. history, Goodwin brought up the pre-Civil War partisanship and recalled the caning of Sumner. Referring to Congressman Brooks, she added: "But the most important thing is, in the South, he was made a hero just as Kavanaugh has been made a hero now."

She then recounted that "it mobilized the anti-slavery sentiment in the North -- they got stronger," and added: "The Republican party -- the party of Lincoln then -- produces Abraham Lincoln. So, if we can awaken from this new low and citizens can get active again, we can make something from this moment. I believe it."

Maher soon responded: "When you said he was a hero in the South, it reminded me of the guy who heckled Obama and said, 'You lie,' and then he was a hero in the South."

Smiling, he added: "Maybe the South is the problem."

Goodwin laughed and cracked: "Maybe we should have let them go," before having second thoughts about her quip and adding, "No."