Manufacturing — that is, the business of making stuff — has changed significantly over the past half-century. Perhaps you’ve noticed. While America’s share of industry has constricted, with fewer people needed to perform the same amount of work as in the past, it’s not quite time to start eulogizing.

But the way the presidential candidates have been talking about reviving manufacturing jobs has not been very enlightening, and in some cases they have been willfully obtuse. Their statements are meant to appeal to disaffected workers, but they both oversimplify the problems and ignore the real source of trouble.

Donald J. Trump, the Republican front-runner, has promised to bring manufacturing jobs back to American workers from abroad. “They can’t get jobs, because there are no jobs, because China has our jobs and Mexico has our jobs,” Mr. Trump said in his campaign announcement speech in June. (He neglected to mention that his own line of neckties is fabricated in China.)

Mike Huckabee, the former Arkansas governor, seems to regularly misconstrue the state of American manufacturing — more than any other candidate. At the undercard debate in Milwaukee on Nov. 10, Mr. Huckabee explained that the United States has lost five million manufacturing jobs since 2000: “The reason they don’t have jobs is because their jobs are in Mexico, they’re in China, they’re in Indonesia,” he said, referring to American workers. While that is certainly true for some of the jobs lost, outsourcing is not the main driver of domestic job loss.

Republicans aren’t the only ones obsessing over reclaiming these factory jobs. Last month, Hillary Clinton mentioned factory closings when she released her own plan to restore manufacturing jobs through a network of tax credits and federal funding for research. Senator Bernie Sanders, meanwhile, in criticizing the Trans-Pacific Partnership, has argued that such international trade deals are to blame for the loss of manufacturing jobs in this country.

The problem with this sort of rhetoric is that a lot of the manufacturing jobs the United States lost over the past 50 years didn’t go overseas; they simply disappeared with the advent of new technology.

James Sherk, a research fellow in labor economics at the Heritage Foundation, said the trend in machines taking over factory work that was previously done by humans has been going on since the 1950s. But for presidential candidates, it’s a lot easier to blame other countries rather than robots.

“It’s those basically rote, repetitive tasks where you’re fixing the same thing,” he said. “It’s very hard to imagine any of those positions coming back. Basically, a robot is a lot more affordable than a human employee.”

The skills needed to work on a factory floor today are quite different than they were 20, 10 or even five years ago. Don’t blame stingy companies or over-regulation by the government; blame the rapid progress of technology.

Mark Muro, the policy director of the Brookings Institution’s Metropolitan Policy Program, said candidates should recognize that because of advances in technology, manufacturing simply does not employ as many people as it once did. Then again, that level of honesty doesn’t make for as much of a feel-good message.

“My fear is that the Republicans to date may not fully understand what modern advanced manufacturing is,” he said. “It’s not necessarily thousands of people pouring into the plant as in the old days.”

Instead of talking down to blue-collar workers, candidates should admit that trying to restore manufacturing to what it once was in this country is not an attainable, or even a desirable, goal. This is not to say the government should not work to bring jobs back to the United States, or that manufacturing as an industry is not valuable to the American economy. But many of the jobs politicians want to restore aren’t on the table anymore.

Unfortunately, when talking about how they would increase manufacturing, most of the candidates have not reached beyond platitudes and into the realm of reality. And some of the points they have made have been baffling. At the November Republican presidential debate in Milwaukee, Senator Marco Rubio stressed manufacturing’s role in the economy, while espousing a curious notion of how the new economy works. “If you raise the minimum wage, you’re going to make people more expensive than a machine,” he said. “That means all this automation that’s replacing jobs and people right now is only going to be accelerated.” (He went on to wax poetic about welders versus philosophers.)

It sounded as if Mr. Rubio believed employers should suddenly realize that machine labor is cheaper than human labor — though that’s been the case for a long time. Machines are cheaper than people, marginal wage increase or not. Yet Mr. Rubio has a point: Automation has fundamentally changed the manufacturing industry. We don’t, however, need to respond to the shrinking manufacturing job market by becoming all-out technophobes.

A few examples of solutions currently underway: In Delaware, high school students can participate in a program aimed at preparing them for modern manufacturing jobs. Some academic hubs like Cambridge, Mass., and Raleigh-Durham, N.C., are set up as innovation districts, where companies and research institutions can commingle with smaller start-ups and job seekers.

There’s no easy answer on how best to foster innovation, though. Even the most enticing tax incentives are unlikely to make companies fire their robots and hire back assembly-line workers. Some of the burden lies with American companies to bring production back home — which actually could be less of a burden than they might think, according to some economists.

The manufacturing sector drives 69 percent of all business-related research and development in the country. The findings of that research and development — like innovations in 3-D printing and the so-called Internet of things — ripple across industries. Employing more American workers also gives them more buying power, which is good for the economy as a whole.

Americans are world-class consumers. Since the recession, our appetite for buying stuff has grown. In the last quarter of 2014, consumer spending in the United States rose 4.3 percent — the fastest rate of growth since 2006 — though spending has slowed since then. And the University of Michigan’s index of consumer sentiment rated consumer confidence in 2015 at 92.9, the highest rating posted since 2004. Still, it’s unclear whether Americans would be willing to shell out more money for a product made by their neighbors than one made halfway across the world.

“We have yet to prove that American consumers are willing to pay a premium for products sourced in the U.S.,” said Willy C. Shih, a professor at Harvard Business School and a co-author of the book “Producing Prosperity: Why America Needs a Manufacturing Renaissance.” “The bottom line is, what product do they put in their shopping basket in the store?”

No candidate wants to be painted as anti-manufacturing, which may account for this lack of honesty about where all the manufacturing jobs have gone. When the moderator Sandra Smith dared to suggest during the Nov. 10 undercard debate that the United States is moving away from “a manufacturing economy to a services-based, technological economy,” Mr. Huckabee quickly shot her premise down. “I don’t know why we have to move away from manufacturing,” Mr. Huckabee replied. The audience applauded.

Mr. Huckabee is right; the United States doesn’t “have” to move away from manufacturing. It’s just that advancing economies like this one inevitably sacrifice some labor for innovation, just as the United States and other developed countries did over the past century when it came to agriculture.

If we’re going to move away from anything, let’s leave behind stock stump speeches on factories. They’re not going to get anyone a job — especially not in the White House.