Washington (CNN) President Donald Trump's closing argument for November 2018 is a lot like his opening argument in June 2015 . Bad people -- murderers, rapists -- are coming up from the border, and he alone could protect the country.

All the conventional wisdom of 2016 was that Trump's message was really all about the economy. Turns out, his argument then and his argument now is really about race, culture and American identity.

Take a look at his schedule, as he tries to stave off a possible blue wave, by ginning up his base: He is set to go to the border and take a firm stand against the caravan of South American migrants who are months away from reaching the border. He is also mulling an executive order in an attempt to subvert the Constitution and end birthright citizenship.

It's not the tax cuts, the Supreme Court picks, the rollback in regulations -- it's the culture war. More bluntly, it's the "white" part of his white working-class base that Trump, a master of identity politics, understands so well.

Author Sarah Smarsh, in her book, "Heartland: A Daughter of the Working Class Reconciles an American Divide," takes a deeper dive into this key demographic group.

Her book looks at her experiences growing up white, poor and in rural America as part of a group she said the media frames as a "weird group that somehow simultaneously has racial privilege and economic disadvantage."

She said the media, even in our almost anthropological fixation on this group, often get it wrong because of class blind spots among others.

Female characters, matriarchal families and single mothers loom large in her story, whereas most conversations about this group, "default to a male voice" she said.

"The social conversation so often equates rural America or the white, working class with men in factories wearing tool belts," she said. "The men who raised me wear tool belts, some of them work in factories. Same goes for the women."

'Otherization'

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I reached out to her recently to talk about her book, rural America and the "white working class," a phrase she said she never heard growing up in Wichita, Kansas.

"It's not a way that we ever refer to ourselves in a million years," she said. "This seems to be a notion that has been constructed by an overwhelmingly upper-middle-class white media for talking about a piece of their own race that nonetheless feels other to them."

This "otherization," she said, allows for a kind of misdirection that ends up locating racial anxiety in a particular place and among a particular class, rather than more broadly.

"White Americans at every economic rung came out for Trump at about the same numbers, with some distinctions if you break things down by college degree," she said. "My critique is not to deny that racism and xenophobia and a sense of one's power in our society being threatened is a piece of the puzzle, what I want to make sure we are saying is that this isn't a problem about poor people, this is a problem about white people."

Still, she said, the focus on the racial grievances and conservative leanings among rural white voters in what is often referred to as "Trump country," erases the social, political, racial and political diversity of a huge swath of the country.

"A lot of these small towns have accepted and embraced the fact that they will have to get with the demographic trends of the country," she said. "It's not just the racist white guy at the diner. There is a whole political spectrum."

Both sides of the divide

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Smarsh, who voted for George W. Bush in 2000, and is more liberal now, says she sees herself as having occupied both sides of the political divide. She sees her book as a way for people across political lines to understand their fellow Americans.

"There is such a starvation and thirst for any acknowledgment, that the first person to waltz in has a greater chance at success," she said. "He is in those places, talking in economic terms, and already has the monopoly on the place because nobody has done it recently."

Democrats, Smarsh said, too often don't validate career paths that don't involve college, and assume upward mobility involves re-training or movement into the "jobs of the future" like tech and a more professional trajectory.

"It is affirming for someone to hear someone say, what you've got going is just fine. It could feel like, my whole life people have looked down on me when I go to city hall with oil on my jeans, and now someone is saying, you do good work," she said, parroting the kind of message Trump gives to his base.

"If a Democrat or anyone just goes to the damn place and sits down and looks them in the eye says, I am present because I want to hear your story and tell you about these ideas I have," she said. "When we write off half the country, or more, as supposed red states and leave them for political dead, it's not a surprise that we have the outcomes that we do."