Star-spangled blowup? Divided United States commemorates 250th anniversary

The world’s longest-running democracy is celebrating its 250th anniversary. Quite the milestone for a United States that to many Europeans still seems like a new world. Since 1789, it’s been governed under the same constitution, a timespan where here in France, we’ve had five republics, three monarchies and three dictatorships if you include Nazi occupation. So what is the significance of this Fourth of July?