MSNBC’s Chris Hayes joins MSNBC’s Ari Melber to discuss his new book “The Sirens' Call: How Attention Became the World's Most Endangered Resource,” and Donald Trump’s battle for constant attention. (T ...

As Donald Trump testifies and defies limits on presidential power, MSNBC’s Ari Melber delivers a special report on federalism and the Founders' efforts to prevent authoritarian rule, emphasizing ...