Four-star Admiral William H. McRaven discusses the imminent withdrawal of U.S. troops from Afghanistan, the current threat level from Iran, and the heroic virtues he details in his new book, "The Hero Code: Lessons Learned from Lives Well Lived."

In a special edition celebrating Independence Day, four-star Admiral William H. McRaven shares stories of heroism from his 37 years of service to America, including details behind the capture of Saddam Hussein and the killing of Osama bin Laden.