YAMHILL, Ore. — We like to boast of America as the “land of opportunity,” and historically there is truth to that.

“We have never been a nation of haves and have-nots,” Senator Marco Rubio once declared. “We are a nation of haves and soon-to-haves, of people who have made it and of people who will make it.”

That’s a lovely aspiration, the vision that brought Rubio’s father to the United States — and my father, too. Yet I fear that by 2015 we’ve become the socially rigid society our forebears fled, replicating the barriers and class gaps that drove them away. That’s what the presidential candidates should be debating.

Researchers have repeatedly found that in the United States, there is now less economic mobility than in Canada or much of Europe. A child born in the bottom quintile of incomes in the United States has only a 4 percent chance of rising to the top quintile, according to a Pew study. A separate (somewhat dated) study found that in Britain, such a boy has about a 12 percent chance.

By another measure, “intergenerational income elasticity,” social mobility is twice as great for Canada as for the United States.

Alan Krueger, a Princeton economist, has noted that in the United States, parents’ incomes correlate to their adult children’s incomes roughly as heights do. “The chance of a person who was born to a family in the bottom 10 percent of the income distribution rising to the top 10 percent as an adult is about the same as the chance that a dad who is 5 feet 6 inches tall having a son who grows up to be over 6 feet 1 inch tall,” Krueger observed in a speech. “It happens, but not often.”

I’ve been reflecting on this because of a friend in my hometown, Yamhill, Ore. Rick Goff was smart, talented and hard working, but he faced an uphill struggle from birth; I wrote about him last year as an example of the aphorism that “talent is universal, but opportunity is not.”

And now Rick is dead. He died of heart disease last month in his home in Yamhill at age 65.

I visited him the day before he died, as he was pained and struggling to walk, and I keep thinking of his prodigious talents that were never fully deployed because, in the United States, too often the best predictor of where we end up is where we start.

Rick, who thought he was one-eighth American Indian, pretty much raised himself, along with his brother and two sisters. His mom died when he was 5, and his dad — “a professional drunk,” Rick once told me — abandoned the family. A grandmother presided, and the kids hunted and fished to put food on the table.

School might have been an escalator to a better life, for Rick had a terrific mind, but as a boy he had an undiagnosed attention deficit disorder and teachers wrote him off. In the eighth grade, the principal punished Rick for skipping school, by suspending him for six months. Rick was thrilled. By 10th grade he had dropped out for good.

Rick worked in lumber mills and machine shops, then became a talented custom painter of cars. After his hand was mashed in an accident, he survived on disability and odd jobs. His phone worked when he had enough money to pay the bills.

He married twice and divorced twice, raised children as a single dad, and was a loyal friend to everyone around. A few years ago, Rick was slowly mending from a serious illness, dependent on a crucial medicine. Then he abruptly weakened and had to be hospitalized.

It turned out that his ex-wife’s car had been towed and she had needed to pay a fee to get it back. So Rick had given her $600 and skipped the medicine. That’s what put him in the hospital.

And, yes, that was for his ex-wife.

Last year, I wrote a series titled “When Whites Just Don’t Get It,” about race gaps (the reaction was not entirely enthusiastic!). I also think that many successful Americans “don’t get” the income gulf.

Sean Reardon of Stanford University has calculated that the race gap in student test scores has diminished, but that the class gap has widened. A half-century ago, the black-white test score gap was 50 percent greater than the gap between the richest 10 percent and the poorest 10 percent. Now it is the other way around, with the class gap almost twice that of the race gap.

Consider that 77 percent of adults in the top 25 percent of incomes earn a B.A. by age 24. Only 9 percent of those in the bottom 25 percent do so.

Yet as Tim Wise notes in a forthcoming book, “Under the Affluence,” there’s an “increasingly vituperative narrative of cruelty” to those at the bottom.

The musician Ted Nugent once suggested that the “takers” in society are “entitlement chumps” and “gluttonous, soulless pigs.” The conservative author Neal Boortz compared the poor to toenail fungus.

Sure, entitlements are a legitimate issue for debate. But if you’re troubled by publicly subsidized meals, what about the $12 billion in annual tax subsidies for corporate meals and entertainment? And if you want to see a real scam, how about those zillionaires who claim huge tax deductions for donating art to their own nonprofit museums, which aren’t even open to people dropping by?

I hear from people who say something like: I grew up poor, but I worked hard and I made it. If other people tried, they could, too. Bravo! Sure, there are extraordinary people who have overcome mind-boggling hurdles. But they’re like the N.B.A. centers with short parents.

Remember that disadvantage is less about income than environment. The best metrics of child poverty aren’t monetary, but rather how often a child is read to or hugged. Or, conversely, how often a child is beaten, how often the home descends into alcohol-fueled fistfights, whether there is lead poisoning, whether ear infections go untreated. That’s a poverty that is far harder to escape.

Some think success is all about “choices” and “personal responsibility.” Yes, those are real, but it’s so much more complicated than that.

“Rich kids make a lot of bad choices,” Professor Reardon notes. “They just don’t come with the same sort of consequences.”

Rick acknowledged that he had made bad choices. He drank, took drugs and was arrested about 30 times. But he also found the strength to give up alcohol when he felt he was turning into his father. What distinguished Rick wasn’t primarily bad choices, but intelligence, hard work and lack of opportunity.

So let’s just drop the social Darwinism. Success is not a sign of virtue. It’s mostly a sign that your grandparents did well.

Meanwhile, more children in America live in poverty now (22 percent at last count) than at the start of the financial crisis in 2008 (18 percent). They grow up not in a “land of opportunity,” but in the kind of socially rigid hierarchies that our ancestors fled, the kind of society in which your outcome is largely determined by your beginning.

Now, that’s what the presidential candidates should be discussing.