Trump's attack on Ilhan Omar is no surprise -- he's trafficked in racism his whole life: biographer
Donald Trump speaking at CPAC 2011 in Washington, D.C (Gage Skidmore/Flickr)

In a column for Bloomberg, Tim O'Brien -- the author of "TrumpWorld" -- said the racist attack that Donald Trump made on four Democratic lawmakers who also all happen to be women of color, should not surprise anyone with a passing familiarity of the president.

According to O'Brien, racism has been a centerpiece of Trump's life going back to when he was just starting out in his family's real estate business.

"Last Sunday, President Donald Trump suggested that four Democratic congresswomen of color, three of whom were born in the U.S., 'go back' to their ancestors’ countries. Despite a broad public outcry about the leader of the free world unleashing a timeworn racist trope, Trump refused to apologize or back away from his comments," O'Brien wrote, before adding, "Trump’s defenders have blamed the media and his political opponents for the backlash, and the president himself tweeted this week that 'I don’t have a Racist bone in my body!' If Trump’s racism isn’t in his bones, then it’s likely to be found in his heart because he’s been awash in it for decades."

With that, O'Brien documented the 14 instances of Trump's racism, from discriminating against renters based on race, attacking opponents based upon their ethnicity, his infamous attacks on the Central Park Five and, of course, launching his presidential campaign by calling Mexicans "rapists."

"All this preceded the events of this week and there’s no reason to believe that the president is chastened. Someone who was authentically compassionate and not a racist would be horrified to be accused of racism; an apology would’ve been prompt," O'Brien wrote. "Yet Trump bridled and has yet to apologize to anyone. That’s because he doesn’t care, because this is who he is."

He then warned of more to come because Trump can't help being who he is.

"The North Carolina rally is a just a taste of how craven the president is prepared to be to retake the White House. The path he’s on will test the country’s morality, decency and ideals," he lamented.

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