Few technological breakthroughs have had the social and economic impact of the automobile. It changed America’s geography, spawning suburbs, shopping malls and sprawl as far as the eye could see. It redefined how we work and play, from the daily commute to the weekend trek to the beach. It expanded the heavy industry — steel-making, car production — that made the Midwest the economy’s epicenter for decades. And, finally but not least, the car became the quintessential symbol of American mobility, status and independence.

Now there are signs that the car and its many offshoots (SUVs, pickup trucks) are losing their grip on the American psyche and pocketbook. The car culture may be dying or, at any rate, slumping into a prolonged era of eclipse. The only question is whether the signs of change can be believed. It’s not clear.

Young Americans, particularly millennials (ages 18 to 35), have lost their zest for buying and driving cars, it’s said. Once upon a time, getting your driver’s license — typically at 16 or 17 — was a rite of passage. You were liberated from dependence on the parental chauffeur. It was a big step toward adulthood. But this landmark no longer seems to matter so much.

Just recently, the Federal Highway Administration (FHWA) published figures — first reported on the Atlantic magazine’s CityLab website — indicating that the number of licensed drivers 16 or younger in 2014 had dropped 37 percent since 2009 and, at 1.08 million, was “the lowest number since the 1960s.”

More impressive, the trend seems long term. A report from the Highway Loss Data Institute cites studies showing that from 1983 to 2010 the share of 16-year-olds with a license fell from 46 percent to 28 percent ; over the same period, the share of licensed 17-year-olds declined from 69 percent to 46 percent .

Theories abound to explain this shift. One emphasizes cost; it’s too expensive to own a car, especially after the high unemployment and meager wage gains of the Great Recession. Uber and other on-demand transportation services make this choice more practical.

Other theories focus on lifestyles and values. Young Americans “just don’t think driving is cool — or even necessary — anymore,” said Fortune magazine. Cars pollute, contributing to global warming. Millennials disapprove. They are said to prefer cities where they can walk, bike or use buses to get to stores, restaurants and jobs.

The most fascinating theory is that the Internet has displaced the automobile. Both are social instruments, it’s argued. Instead of going to the mall, teens and others stay in touch through social media and texting. It’s cheaper and more convenient.

Maybe. But a new study by Federal Reserve economists Christopher Kurz, Geng Li and Daniel Vine throws cold water on these and other generational explanations. It suggests that most potential young buyers couldn’t afford a new vehicle or didn’t want to incur the debt and operating expenses of doing so. Economic considerations dominated.

The study confirmed that new vehicle sales to younger consumers (16 to 34) weakened after the Great Recession. From 2000 to 2010, their share of sales fell from 28.6 percent to 19.8 percent. By 2015, it had recovered slightly to 22.6 percent. But declines for some other age groups were larger. Among 35-to-49-year-olds, the share of sales slid from 39.2 percent in 2000 to 29.9 percent in 2015. Indeed, the only age group with big increases were those 55 or higher.

When the economists adjusted the buying behavior of different age groups for income, employment status and some demographic factors (marriage, children, education, race), they found few differences. “Economic factors,” as opposed to “permanent shifts in tastes and preferences,” shaped car sales.

Since 1960, ordinary drivers’ travel distances have nearly doubled, from 7,700 miles annually to 14,100 miles in 2014, reports the FHWA. Still, the car culture no longer exerts the stranglehold on the American consciousness that it once did. There is too much congestion for that. Perhaps today’s millennials will break new ground, even if it is the consequence of their predicament — debts elevated, incomes squeezed — rather than a cause. More of them may decide that city living or clustered suburban communities are more appealing than traditional suburbs. Gentrification may defeat commuting.

Or perhaps not. We simply don’t know. What we do know is that we are, to a large extent, prisoners of the past. The car created today’s residential geography, and it cannot be repealed simply or swiftly.

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