Donald Trump supporters stand on the sidewalk as Hillary Clinton's campaign buses make their way to an event at Johnstown Wire Technologies in Johnstown, Pennsylvania. AP There's a reason why "Hillbilly Elegy," J.D. Vance's memoir, is at the top of the New York Times nonfiction best-seller list. You might call the book a loving indictment of the hillbilly culture that Vance grew up in and then escaped from, attending Yale Law School and becoming a principal at a San Francisco tech-venture fund.

A lot of people like the book for its insights into what the white working class sees in Donald Trump and his promises to restore American greatness in the face of malevolent outsiders.

But what I liked best about the book is how it engages with what I see as one of the most important and difficult social-policy questions of our time: How do we unstack the deck and, at the same time, get people to take ownership over improving their own lives and communities even when they reasonably believe that the deck is stacked against them?

Vance has a few policy recommendations to improve the lives of the white working class — in particular, he thinks that child-protective-services departments need reform. But he's a conservative who believes that the government has limited scope to fix the culture, so mostly his prescriptions are about private behavior: Working-class whites from the Rust Belt to the South need stronger community institutions like churches, more positive attitudes toward work, and less defeatism that assumes their fate has been sealed by far-away forces.

Most problematically, he notes that even an accurate belief that forces beyond one's control are causing one's disadvantage can lead to hopelessness and greater disadvantage.

For example, Vance's mother has fought an ongoing battle with opiate addiction. She contended that addiction is a disease for which she shouldn't be judged, a sentiment Vance found absurd and destructive even when he was 13. As an adult, he notes that his mother was sort of right: There are genetic factors that predispose some people for drug addiction. But he was also right in that addicts who view their addiction as a disease do worse at kicking the habit.

More broadly, Vance observes economic defeatism from working-class whites who blame foreign companies for moving good jobs overseas and politicians for prioritizing the needs of other groups.

Their complaint is not entirely wrong. Economic research is making increasingly clear that increased trade with China over the last 25 years had significant, negative effects on workers in certain parts of the country, like the industrial town in Ohio where Vance grew up, though perhaps not as negative as widely believed in those regions.

And the policy failures that led to the 2008 financial crisis caused hits to workers' wealth and income all over the country.

But Vance describes his neighbors using those external forces as an excuse to give up — coworkers who were routinely late to jobs they desperately needed to support their families, and an acquaintance quitting his job because he didn't like getting up early and then taking to Facebook to bemoan the "Obama economy."

I have had mixed feelings over the last eight years as the American political debate over the economy has become more focused on the institutional and external forces holding workers back.

On one hand, there were very good reasons for this shift in focus. The economic fragility demonstrated by the 2008 crash provided a good argument for a more generous safety net. A long spell of elevated unemployment meant that many more people than usual would fail to find work even if they really wanted it, a situation that called for a long period of extended unemployment benefits.

Amazon Republican arguments during the post-crisis period, embodied in the paeans to entrepreneurship that made up Mitt Romney's campaign — "You did build that!" — fell flat with many Americans who felt that the key reason they were falling behind was not an insufficient work ethic.

But rather than shifting to a message of compassionate uplift, Trump has taken Republicans from blaming the lazy 47% to blaming hostile outside forces for America's lack of economic greatness.

In the long run, I worry that if the idea that people are responsible for their own prosperity is not a central economic theme for either party, then Americans will come to feel like they're not getting what Republicans or Democrats promised them — and that all the fault for their troubles lies externally, so they need not try.

Ideally, what we would have is a public policy that is strongly informed by the fact that often individuals fail and groups fall behind for reasons of no fault of their own, and that devotes extensive resources to reducing and compensating for the institutional forces that hold people down. At the same time, we would have a civic culture that places high expectations on people to improve their own economic fortunes, and to put their children in a good position to promote theirs.

I worry that these two goals are in conflict.

The ethic of rugged individualism can be an excuse for stripping the safety net. If people can pull themselves up by their bootstraps, then why do we need all these programs? At the same time, a political discourse that is overly focused on the external causes of misfortune can make people feel like the deck is stacked against them, so why even try?

This circle would be easier to square if policy elites had performed better over the last 15 years, and could more credibly say that they had created the public institutions necessary for people to improve their own lives.

Things could be worse: We could have higher unemployment and slower economic growth, like many countries in Europe. But voters are not wrong to insist that things could also be better.

I don't know what to do about it, but "Hillbilly Elegy" is a good book that does a lot to diagnose the problem.