What makes Trump's tweets racist? A historian explains

When President Trump tweeted on Sunday that "'Progressive' Democratic Congresswomen" — an apparent reference to Reps. Alexandria Ocasio-Cortez, Rashida Tlaib, Ilhan Omar and Ayanna Pressley, who are all women of color — should "go back" to their countries, the backlash was swift. It also sparked another conversation: What makes something racist?

Ibram Kendi, a professor and director of the Antiracist Research and Policy Center at American University, joined "CBS This Morning" to address that question from a historical perspective and discuss whether racist actions or words make someone a...