'This Vast Enterprise' gives new accounts of the Lewis and Clark expedition

Two years, eight thousand miles, and according to a new book, a lot more heroes than just Lewis and Clark. On this episode, we talk with historian and author Craig Fehrman. He spent five years chasing down the real story behind the famous expedition, and found it wasn't just their story. His new book, 'This Vast Enterprise: A New History of Lewis & Clark,' rebuilds the history through 10 different voices, exploring new perspectives of American history.