On the short form of the great American road trip, local accents, and the narcissism of small differences

America is a land rich in two-hour road trips: Pittsburgh to Cleveland, Los Angeles to San Diego, Memphis to Little Rock, Philadelphia to Baltimore. A two-hour road trip is far enough that it isn't "everyday", but it's close enough that it wouldn't be crazy to leave work at 5:00, have an out-of-town dinner at 7:00, and be home again by 11:00.

■ Yet it's a distance far enough that some differences will be evident. It's usually far enough to cross into a different media market, often a different state, and frequently even into at least a modestly different local accent of English.

■ Things do not change merely at the points of embarkation, though. In the course of a two-hour road trip, the traveler will likely pass through at least two dozen micro-cultures hidden along the route. Any place can have a micro-culture if it has some kind of local history, a community school district, perhaps a well-regarded local restaurant, or maybe even an idiosyncratic local pronunciation or two that distinguishes the in-group from outsiders.

■ Even smaller than that, micro-cultures grow up around homeroom classes, Bible study groups, and drone-flying clubs. The unwitting traveler breezing by at 70 mph on an Interstate highway generally takes little or no notice of them along the way, but they remain there regardless. And the differences they celebrate are not just innocent, they are often the fabric of an American ethos.

■ We don't have to be homogenous to get along. In fact, it's desirable that we distinguish our communities from one another in a spirit of good-willed competition, as long as we avoid succumbing to the narcissism of small differences. A healthy, evenly-matched rivalry can be a great instigator for self-improvement.

■ Even more broadly, though, an appreciation for those granular differences between places only a few miles apart ought to encourage a sense of modesty about what ought to bind the members of a continental-scale nation.

■ It shouldn't make us modest in our ambitions -- sending astronauts to the Moon is a distinctly immodest act -- but it should keep us humble about the extent to which we expect everyone else to adhere to the same rules as ourselves. There is real merit in holding back so that we only expect enforceable uniformity where it truly matters.