Editor’s Note: Michael D’Antonio is the author of the new book “Never Enough: Donald Trump and the Pursuit of Success” (St. Martin’s Press) and is due to be a guest on “CNN Newsroom” Monday in the 10 a.m. hour. The opinions expressed in this commentary are his.

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It wasn't an accident that the billionaire claimed that he didn't know about David Duke, writes Michael D'Antonio

Trump was questioned about the white supremacist 48 hours before primaries in Southern states, D'Antonio notes

CNN  — 

Given a straighforward opportunity to disavow the most dangerous brand of hatred in American history, the man who has declared, “I’m, like, a really smart person” couldn’t do it.

“I don’t know anything about what you’re even talking about with white supremacy or white supremacists,” said Donald Trump in a response to CNN’s Jake Tapper. “So I don’t know. I don’t know – did he endorse me, or what’s going on? Because I know nothing about David Duke; I know nothing about white supremacists.”

Michael D'Antonio

The statement was classic Trump: a chopped salad made out of words. But the two parts were clear. “I know nothing about David Duke,” he said. “I know nothing about white supremacists.” (Trump later tweeted a disavowal.)

Every literate American adult, and certainly anyone running for president, must know that Duke is the former leader of the Ku Klux Klan and that white supremacists promote a violently racist ideology that plagues America.

The 1995 bombing of a federal building in Oklahoma City that killed 168 people, including 21 kids in a daycare center, was associated with if not inspired by white supremacy.

Since 9/11 white supremacists and other domestic terrorists have carried out more deadly attacks on American soil than Muslim extremists. It was a white supremacist who killed nine people at a Bible study at a Charleston, South Carolina, church last summer.

Concern about racist support for Trump arose last week when David Duke said on Facebook that he liked Trump’s stands on certain issues and the way the candidate exposed “lies” perpetrated by the press and believed he will ensure “that White-Americans are allowed to preserve and promote their heritage and interests just as all other groups are allowed to do.”

When first informed of Duke’s support on Friday, Trump didn’t have any trouble recognizing the name. “David Duke endorsed me?” he said. “OK, all right. I disavow, OK?” This makes sense, given the fact that Duke is notorious for hate-mongering and Trump named him years ago when he explained why he dropped out of the old Reform Party. Back then, and again on Friday, he knew who Duke was and seemed to recognize that he’s political poison.

Trump’s tune changed 48 hours before polls would open for Super Tuesday primaries, many of them in Southern states. Suddenly he was unable to place Duke’s name and he didn’t know a thing about the movement that keeps white racist extremism alive in America.

This from a fellow who is famous for recalling every detail of every deal he ever made and who never forgets those who offend him. If Duke was so bad that his presence drove Trump out of the Reform Party, it’s unlikely he’s forgotten him.

What’s going on here? As someone who has spent many hours with Trump and devoted two years to piecing together the story of his life, I can tell you that Trump is not speaking out of ignorance. He is, as he says, “very smart,” and he understands the effects of what he says. And he has been signaling where he stands when it comes to race for many years.

Before declaring for president, Trump spent much of the Obama presidency as the loudest voice of the “birthers” who repeatedly claimed that Barack Obama was born, not in Hawaii, as documents prove, but abroad. And therefore he was not a U.S. citizen, and not a legitimate president, in Trump’s eyes.