You often hear that there are huge swathes of the country in which it's just not feasible to make changes that will lead to people driving less -- there's no other way to get around! This is often quite true in a literal sense. But oftentimes it would be possible to make non-drastic changes that would still make a difference at the margins. Here's a satellite photo of a swathe of Virginia near Tyson's Corner. You'll note that the housing north of the highway is actually very close to all this non-housing stuff south of the highway. But if you live north of the highway you can't walk to the south of the highway stuff just because the streets aren't designed to make that possible.

The necessary changes would, however, be relatively simple to make and would even provide money and jobs for people in the road-building sector -- it's just a case of making sure that roads actually link up with one another (rather than being cul-de-sacs strung together to reach a handful of arterials) and feature sidewalks or bike paths. People are still going to drive for some -- maybe even many -- trips, but at least some of suburban American's trips could be replaced by walking or biking without radically overhauling neighborhoods or constructing massive new transit systems. Among other things, that would take pressure off the roads and fuel supply, leaving those resources available for trips where there genuinely is no reasonable alternative.