“Unfortunately, there’s one thing we did not engineer,” Mr. Akerson said. “Although we loaded the Volt with state-of-the-art safety features, we did not engineer the Volt to be a political punching bag. And that, sadly, is what it’s become.”

Is this the beginning of the end of the latest experiment in the electric car, whose checkered history goes back to the dawn of the automobile age? Can the electric car survive only with heavy government subsidies and big consumer rebates? Are the Teslas and Fiskers and ActiveEs and Volts and Leafs destined to be the playthings of only rich technophiles with a couple of spare gas-powered cars at home?

Or is this what an emergent technology looks like before it crosses the valley of death?

“Face it, this is not an easy task,” said Brett Smith, assistant research director at the Center for Automotive Research in Ann Arbor, Mich. “You still have an energy storage device that’s not ready for prime time. You still have the chicken and egg problem with the charging infrastructure. That’s not to say it’s not viable over the long run. But the hype is gone and the challenges are still there.”

The market for all-electric and plug-in electric cars in the United States is tiny, amounting to fewer than 20,000 sales last year out of total light-vehicle sales of 12.8 million. Even in optimistic forecasts, plug-in vehicles will account for less than 5 percent of the global market by 2025.

Hybrids that do not require external charging, however, like today’s Toyota Prius and many others already in showrooms, are a growing segment. Forecasters say they could represent as much as 6 percent of the market by 2015 and 25 percent by 2025, in part because they are among the few vehicles currently on track to meet the government’s proposed new fuel economy standard of roughly 50 miles per gallon by 2025.