Valeria Luiselli says that she began writing Lost Children Archive in July 2014, inspired by a road trip to the south-west of the US as the refugee crisis at the Mexican border was coming into visibility. “It became impossible to ignore the reality around me,” she said, and so she started writing.

But the project stalled. Perhaps not surprisingly, as Emma Brockes explained here at the start of the year, the book “started out as an angry screed, overly didactic and too bogged down in politics”. Luiselli told Brockes that she was using the book as “a vehicle for my own rage, stuffing it with everything from children’s testimonies to the history of American interventionism in central America … It just wasn’t working. There’s a different way of assuming a political sense in fiction, I think.”

So she paused. She wrote a book of essays that articulated some of her anger – and then returned to her story in time for publication this year. The opening pages of the finished novel suggest that she found her way by focusing on the human and the personal: “Mouths open to the sun, they sleep. Boy and girl, foreheads pearled with sweat, cheeks red and streaked white with dry spit. They occupy the entire space in the back of the car, spread out, limbs offering, heavy and placid.”

This is one of several lovely (not to mention amusing) depictions of the narrator’s two sleeping children. Passages that help remind us that those lost little ones in the title are not statistics, or dots moving around the map, or bureaucratic expenses. They are beautiful innocent dreamers.

This bridge to the migrant crisis is strengthened as we follow the family on a road trip from New York to Arizona. Their intimate bickering, their jokes and their conversations about audiobooks make them feel close to exactly the kind of literate reader you might expect to pick up a book like this one.

Which makes it all the more jolting when Luiselli reminds us that there are also crucial differences. As the family go further south, they encounter increasing hostility and danger. People go silent when they learn that the narrator is Mexican. Police and authority figures start to exude menace.

We realise that these people who have become our intimates are equally close to the “alien” families who feature on the fringes of the novel. To those who have been trying to cross to the US, who have been interned, have lost their children, or encountered other forms of desperation. And so we realise that but for accidents of birth and fate, we too could be labelled as aliens.

It’s effective – and there’s plenty more to admire in these early pages. There are, for instance, beautiful sentences: “An old lady answered the phone, her voice like a distant fire, crackling its way into my ear.”

There are also a few things to grumble about. Now and again the politics and big ideas feel shoehorned in. News about the migrant crisis comes a little too conveniently over the car radio. Overheard conversations can rather neatly sum up the book’s big themes. The narrator listens in on a book group in Asheville, who decide that “the value of the novel they are discussing is that it is not a novel. That it’s fiction but also it is not.” Aha!

I also had a few doubts in the early pages about the narrator’s youngest daughter. She is supposed to be five, but often feels much older. Would she really want to have a stake in a conversation about whether to listen to On the Road or Lord of the Flies on audiobook?

But soon I was won over. How not to love a girl who responds to one of her parents’ conversational tics by saying “the point is, the point is, the point is always pointy”? There’s also a fantastic running joke about “Jesus Fucking Christ” and who he may actually be. This deeply serious book can be very funny. I especially loved a passage in which the narrator tells someone who loves westerns: “My favourite western is Béla Tarr’s Sátátangó!” This prompts a “terrifying drunken idea”. “Why,” asks the man, “don’t we rent it and watch it together in our house?”

Well, I was roaring. Luiselli explains that the film is seven hours long, but perhaps the joke only really works if you’ve seen a Béla Tarr film? Or, more to the point, if you’ve stopped watching one in despair when you’re three hours in but not even halfway and all that’s happened is that it’s started raining.

While I was laughing, I was also feeling smug for getting the reference. In this way, Luiselli cleverly flatters us. Her narrator shares hundreds of similarly literate and smart allusions and ideas with the gentle ease of one talking to equals. She is never patronising. She always assumes shared values and understanding. She makes readers feel almost as clever as the family we are reading about.

It’s a good trick – and not just that. “The intellectual amplitude and the moral seriousness are fortifying and instructive,” wrote James Wood in the New Yorker. I’d be tempted to go even further. In an age when experts and the intelligentsia are supposed to be the enemy, this celebration of shared culture feels vital. These are our people, we are reminded. And all people are potentially our people. We should hold them close. We should never listen to those who seek to divide them from us and to treat them like aliens.