This is an excerpt from the "60 Minutes" interview. Follow the link at the bottom of this page to view the full interview on CBS. 

H.R. Mcmaster was an eyewitness to the Oval Office tempest that forms President Trump's foreign policy. McMaster was national security adviser for 13 months beginning in 2017 and he brought a world of experience to the job. He graduated from West Point, led troops in combat, served multiple tours in Iraq and Afghanistan. And, on the way to becoming an Army three-star general, he earned a Ph.D. in history. McMaster has written a new book called "Battlegrounds." The title refers to threats faced by the U.S. today and to skirmishes at the White House. The now-retired general is a disciple of neither political party. He told us the last few presidents, not just President Trump, have left the United States vulnerable in the eyes of those who would do us harm.