If we start building infrastructure in our cities again for rail and express buses, you will see things being to naturally be more compact. Business spring up around rail stations, and people who want to live close to one another fill in those spaces and move closer to the city.
The "America is too spread out" argument is total bullshit. At the very least, make the cities have good transport and walkable areas. It can happen in a very short time frame. We lost it in a short time frame. Northern Indiana has the same population density of Scotland, so it can work if we build it. We use to have trains from Nashville to Atlanta. The famous "Chattanooga Choo-choo" doesn't even have an AmTrak anymore.
Transportation is the largest factor in the ability of people to move up from poverty. This isn't some subjective statement. There are tons of objective studies to support this[1].
The idea that you need to own a car (and insurance an maintenance) in most of America is pretty insane. A car shouldn't ever be a necessity. Associating it with freedom, as the American car companies have, and buses with poverty, is ass fucking backwards.