On this date in 1872, Ulysses S. Grant signed legislation preserving the splendors of Yellowstone. In the process, President Grant helped create the template for a vast national park system that Western writer Wallace Stegner once described as "the best idea" America ever produced.
Although I dearly love Yellowstone and America's other "crown jewels," including Yosemite (the first national park I visited as a boy, and a place set aside, during the Civil War, by Abraham Lincoln), I'd describe freedom as America's best idea. Come to think of it, Lincoln and Grant had much to do with preserving, and extending, that concept as well.
Carl M. Cannon is the Washington bureau chief for RealClearPolitics. Reach him on Twitter @CarlCannon.