Trump: Elon ‘just went CRAZY’

President Trump and Elon Musk’s public feud has escalated as both billionaires post on social media platforms about one another. NBC News’ Kelly O’Donnell reports the latest from the White House. New York Times White House Correspondent Tyler Pager and Professor of Economics and Public Policy at the University of Michigan Justin Wolfers join Katy Tur to react to the heated back and forth.