Bernie Sanders: U.S. under Trump faces "unprecedented level of danger"
Across the U.S., tens of thousands have been attending rallies held by Sen. Bernie Sanders, who has said that the nation is moving rapidly toward what he calls an oligarchy influenced by billionaires. Sanders sits down with "Sunday Morning" national correspondent Robert Costa to discuss the senator's criticism of the Trump administration; the influence of Elon Musk and other wealthy backers in Washington; the pressure campaign waged by the White House against some law firms; and why, at age 83, Sanders continues to fight.