 Coming up, as we celebrate the 4th of July, a look at how far we've come. We're focusing inward on what divides us, not on what unites us. A presidential historian on the history of the holiday and why it almost became a July 2nd observance. Plus, a 4th of July tradition that's gotten doggone controversial. Competitors can't promote a rival hot dog, a hot dog that rivals Nathan's Famous.