John Kelly.

Ron Chernow, a historian and author of a newly released biography on President Ulysses S. Grant, said Friday that the president’s chief of staff was wrong to chalk up the Civil War to a failure to compromise.

President Donald Trump’s chief of staff, John Kelly, said Monday that “the lack of an ability to compromise led to the Civil War.”

That’s wrong, Chernow said.

“If he’s looking for an example of failure to compromise in our history, he really turned to the wrong place,” Chernow told host Tom Ashbrook in an On Point interview Friday about his book, “Grant.” “And I think unfortunately we have to call him out on it.”

Added Chernow: “My reaction in terms of the compromise statement is that for 75 years, the country had been doing nothing but compromise.”

You can find the full hour on Chernow's book here.

All you have to do to find out what the war was really about, Chernow said, is to look at what Confederate leaders, like Confederate Vice President Alexander Stephens, were saying: that the Confederacy was based on the idea that the natural state of black people was in slavery.

Kelly, a retired four-star Marine general, also said during a Fox News appearance that Confederate general Robert E. Lee was an “honorable man.” But Lee, who didn’t capture a single Union army as a battlefield general, once said that blacks needed “painful discipline… for their instruction as a race” and that they were better off in America than they were in Africa.

“I think we have to see Lee accurately in his totality,” Chernow told host Tom Ashbrook. “He was a strong believer in the basic principles of the confederacy.”

Chernow also said that President Trump’s comments after the Charlottesville, Virginia white supremacist rally – at which a counter-protestor was killed, allegedly by a white supremacist – were a “depressing case of history repeating itself.”

Trump said after the deadly rally that there was blame to go around on “both sides.”

In much the same way, Chernow said, some areas of the south started to rely on a revisionist history. That new narrative said the south and the north not only both fought with valor, which Grant believed, but both fought for equally noble principles, which he did not.

The words of Grant himself after the first shots of the war seemed especially relevant today: “There are now only two parties – traitors and patriots,” Grant said.