Should U.S. president be authorized to launch nuclear bomb?

On August 6, 1945, the United States dropped the first atomic weapon on Hiroshima, Japan. Seventy-five years later, the NewsHour revisits how the president became the sole authority on when nuclear weapons are used. Nick Schifrin reports and talks to former Secretary of Defense William Perry, co-author of "The Button: The New Nuclear Arms Race and Presidential Power from Truman to Trump."