Why have few nations practiced democracy

While the U. S. has sometimes failed to practice true democracy, the belief in 'government of the people, by the people and for the people' remains critical to the nation's identity. But not every country has a democracy because the system isn't as great as we think, and oppressive leaders are tough to overthrow. That's according to NYU professor of politics Alastair Smith. Host Michel Martin speaks with Smith to learn more about his theory.