On Labor Day 2017, the polls were dismal for President Trump -- according to Real Clear Politics, his average approval rating was 38.5 percent, and his disapproval rating on average was 56.5 —18 points under water. But after a year of Robert Mueller investigation headlines, porn-star payoffs and strange Twitter rants, Trump's numbers are…up: 42 percent approve, 54 percent disapprove. Not great numbers, but an improvement.

A year of virtually non-stop negative media attacks and self-inflicted political wounds, and the president is more popular? How does that happen? To quote Joe Biden from the 2008 campaign trail, "It all comes down to one three-letter word: 'Jobs.'"

Everybody knows the news of the red-hot Trump economy: Quarterly growth at 4.2 percent (the average under Obama: 1.6 percent) Unemployment is bouncing around record lows. The overall rate is 3.9 percent, and in May of this year, it hit an 18-year-low 3.8 percent—and the lowest rate ever recorded for black Americans.

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But that's only part of the story. After all, more jobs were added under President Obama in his first two years than under President Trump: 3.8 million jobs added in Trump's first 20 months versus 4.3 million jobs added under Obama during the same period. This is due in part to Obama taking over an economy on the rebound from the Great Recession—the "nowhere to go but up" effect. Still, on paper today's job improvement is a continuation of a trend already in place. Why is it resonating to Trump's benefit?

In part because Trump's job growth is different. President Trump campaigned in the Rust Belt and told men—in particular, blue-collar, non-college-degree-holding men—that their economic future could be brighter, too.

In 2013, well into the Obama economy, 18 percent of Americans workers said they feared it was very or somewhat likely they would lose their job in the next 12 month. This Labor Day, that number is down to 11 percent.

Since 2013, the number of people who say there are plenty of jobs available in their communities has doubled, from around 25 percent to 50 percent today.

In August of 2014, 30 percent of Americans said it was a good time to find a quality job. In August of 2018, it's 65 percent.

After years of talk about the benefits of globalism and new technology for white-collar Americans, Trump told the "forgotten Americans" they would be forgotten no more, and to a degree, he's kept that promise.

The top two sectors of job growth under Trump: not financial analysts or college administrators, but the mining and logging industry (up 13.5 percent since the election), along with construction and transportation. The Labor Department expects jobs in construction and extraction to grow 11 percent from 2016 to 2026.

In fact, growth in manufacturing jobs over the past year was greater than at any time since 1995. Blue-collar work for blue-collar skills and blue-collar guys.

This comes after years of being told by Washington elites and the media that their way of life was obsolete, that the people J.D. Vance wrote so eloquently about in "Hillbilly Elegy" had no future. Then Trump shows up, tells them they have reason to hope, and jobs—their kind of jobs—follow. Is it any surprise those workers and their families are sticking with Trump?

And then there's the way President Trump talks about jobs and the economy. His current NAFTA fight is a perfect example of how Trump frames the jobs conversation in terms of these traditional laborers, as opposed to the broad, positive impact of increased trade. North America is essentially a $1 trillion trade zone. Much of that trade involves the white-collar economy and high-tech jobs. But when Trump talks, his focus is manufacturing jobs. He's demanding increases in the content in cars that must be made by American workers, putting pressure to raise wages from the low end in Mexico to make American wage earners more competitive.

These are relatively small changes on what, in the big picture, is a tiny part of our international trade. But when these families hears Trump taking on Canada, Mexico and China over trade, they hear him taking on the world for them.

Economists tell us that automation and tech will continue to erode jobs -- growth in manufacturing may be higher now than it's been in decades, but it's still a fraction of what it was in the 1950s. They say the work these families rely on won't be part of our future economy. And they're almost certainly right.

But on this Labor Day, thousands of workers in mining, manufacturing and construction are enjoying a day off from a job they feared they had lost forever. And that's good news for President Donald Trump