America’s long detour away from walkable communities may soon end. The Federal Highway Trust Fund is in trouble. No one seems willing to pay to save it. Depending on how we handle this, we could be better off or worse off.

America has a long history of government-funded infrastructure. British taxpayers underwrote the development of our first ports. Our Founding Fathers built canals. Here in 19th century Georgia, a government rail line gave rise to a little settlement that became Atlanta.

In the early 1900s, government subsidies turned from rail to roads. Atlanta taxed streetcar lines to pave streets. Georgia passed a state-aid highway law in 1908 and began collecting a one cent gas tax in 1921 that rose to six cents per gallon by 1930. Nationwide, the various states’ gas tax collections went from $1 million in 1919 to over $1 billion in 1946. America’s “love affair with the automobile” was not cheap.

Before World War II, road subsidies were not enough to run most private rail operators out of business. Cities’ rail-oriented development fit with the rails like a hand in a glove. Most neighborhoods had grown up near train stations or electric streetcar rail lines. Rail-oriented American small towns and cities preserved the walkability cities had known for thousands of years.

After World War II, planners rewrote standard local zoning codes to force private businesses to provide free parking. New codes required builders to set buildings back from the street behind giant surface parking lots. Counties and cities across the country adopted these “model” codes, which decimated downtowns large and small. But to really make the automobile viable, we needed to spend tax dollars — a lot of tax dollars.

Enter the Highway Trust Fund. Before 1956, the federal gas tax had gone through the general budget and not all of it went to roads. In 1956, the federal government put gas tax proceeds in a “lock box” dedicated entirely to roads, with no gas tax proceeds dedicated to mass transit.

Privately owned mass transit systems, already suffering from the loss of streetcars, began to die off. Most privately owned intercity trains stopped running in 1971, and their assets were transferred to an underfunded Amtrak. Georgia passed a constitutional amendment in 1965 to allow five counties to raise a one cent sales tax for MARTA. In 1971, voters in two of those counties, Fulton and DeKalb, voted for the tax to keep buses running and build a new rail system.

In 1983, the federal government raised the gas tax to 8 cents a gallon for roads, but dedicated only 1 cent per gallon to mass transit. Road building exploded. Georgia’s urban interstates more than doubled from 1,244 lane miles in 1980 to 2,786 lane miles in 1995. MARTA rail, built over almost the same time period, is only 96 miles.

Just as development followed streetcar lines in the 1890s, it followed highways and other roads after World War II. The federal road-building push in 1956 followed the 1954 Supreme Court decision outlawing segregation. As fearful white families fled integrated schools, developers were happy to sell them houses near highway off-ramps.

In the 1980s and ’90s, people of all races were moving further out. The economics made it hard not to. But cities like New York, Boston and Chicago preserved their rail transit through either brilliance or inertia, and saw redevelopment of their core. Cities that started new transit systems like San Francisco, Washington and Atlanta also saw redevelopment.

Most tall buildings in Atlanta are near MARTA stations. Atlanta’s skyline follows the MARTA tracks. For the first 20 or so years of rail service, MARTA-oriented development was commercial. Since the early 2000s, it has been residential as well. A tall thin line of skyscrapers is what our city looks like from a distance. You can reach any part of that skyline on a MARTA train.

It is tempting to let the highway house of cards fall. We could just let everyone “move to MARTA.” That would certainly be a free-market solution. But much of our economy is tied to the freeways, and losing them suddenly would be a shock. Our federal government should properly fund Amtrak, correct the imbalance in road versus transit funding, and give communities time to transition gradually back to a more balanced and sustainable system.

Lee Biola, an Atlanta attorney, is chairman of Citizens for Progressive Transit.