“What I realized many years ago, watching that funeral procession with Mamaw,” wrote J.D. Vance in his bestselling memoir, Hillbilly Elegy, “is that I am a hill person. So is much of America’s white working class. And we hill people aren’t doing very well.”

Vance penned those words eight years ago, and his meteoric political rise since then is the most poignant, improbable, and fascinating of stories — from the familial dysfunction and the grinding poverty of Appalachia to the Marine Corps to Yale Law School to the U.S. Senate.

And now, to the Republican presidential ticket of Donald Trump.

“After lengthy deliberation and thought,” posted Trump yesterday afternoon, while the horrible and nearly catastrophic events of two days prior were still fresh on everyone’s minds, “and considering the tremendous talents of many others, I have decided that the person best suited to assume the position of Vice President of the United States is Senator J.D. Vance of the Great State of Ohio.”

At first glance, Vance doesn’t seem to offer much to Trump electorally. He’s from a state, after all, that Trump has won comfortably in two previous elections, and he doesn’t bring in an obviously broader voter constituency. But when we think more deeply about what a vice-presidential candidate is supposed to do — which is to somehow balance the top of the ticket — Vance checks some important boxes.

Vance is young, 39, exactly half Trump’s age. He’s the first Millennial to appear on a major-party presidential ticket, and, after Mitt Romney, its second venture capitalist. His Marine Corps experience checks another important box, as our next commander-in-chief will need to restore and reconnect with a U.S. military that has been laid low by the woke agenda of Joe Biden. And while Vance is not black or female, his wife, Usha, does bring some additional diversity to the ticket. She’s a fellow Yale Law graduate and the daughter of Indian immigrants. Beyond skin color, though, it’s hard to imagine a greater contrast from bombastic old Manhattan real estate developer to humble young Midwestern hillbilly.

But there’s another powerful dynamic that Vance brings to the ticket: He used to be one of Trump’s harshest critics, and now he’s one of the man’s most articulate advocates.

“I was certainly skeptical of Donald Trump in 2016,” Vance told Fox News’s Sean Hannity last night in a friendly but wide-ranging interview, “but President Trump was a great president, and he changed my mind. And I think he changed the minds of a lot of Americans because, again, he delivered that peace and prosperity.”

The message here to that ever-narrowing band of persuadable 2024 voters? If a Yale Law graduate like J.D. Vance can change his mind about Donald Trump, why can’t I?

In his announcement, Trump went on to trumpet Vance’s accomplishments, then he tipped his hand toward how he’ll employ his running mate: “J.D. has had a very successful business career in Technology and Finance, and now, during the Campaign, will be strongly focused on the people he fought so brilliantly for, the American Workers and Farmers in Pennsylvania Michigan, Wisconsin, Ohio, Minnesota, and far beyond.”

Indeed, if Trump picks off one of those former “Blue Wall” Rust Belt states — Pennsylvania, Michigan, or Wisconsin — the race is over. And Vance’s pedigree makes him perfectly suited for that task.

If the Trump-Vance ticket wins on November 5, it will create a Senate vacancy, to be filled by Republican Governor Mike DeWine. And Ohioans will have a decision to make this November about their other Senate seat, which is currently occupied by a Democrat, Sherrod Brown. Brown might therefore be the most nervous man in America. And the second-most-nervous man might be Senate Majority Leader Chuck Schumer. Because the Democrats control the Senate by a single seat, and there will have to be a lot of ticket-splitters in Ohio if Brown is to survive what is likely to be a powerful turnout for a presidential ticket that includes one of its own sons.

In any case, the Vance pick seems to be one made out of confidence, out of a position of strength. “Trump,” as our Nate Jackson observed, “is thinking legacy, not votes. Vance doesn’t bring in anyone who wasn’t already planning to vote Trump.” Contrast this, for example, with the profound weakness that forced Joe Biden into picking Kamala Harris.

Not everyone on the Right, though, is enamored of the Vance pick. Take the Wall Street Journal editorial board, for example, whom we suspect would’ve rather seen Trump pick Nikki Haley:

Mr. Vance’s selection was urged on Mr. Trump by his son, Don Jr., and seems like a play to pass the Trump mantle to a new generation in 2028. But Mr. Trump’s appeal hasn’t been heritable so far, and it will depend on a successful second term and Mr. Vance’s ability to broaden his adopted MAGA profile. His Saturday tweet blaming Democrats for the assassination attempt on Mr. Trump was at the very least bad judgment that belies Mr. Trump’s new desire to campaign on unity.

Or take National Review’s online editor, Philip Klein. Seemingly doing his best to drive a wedge between the Trump-Vance ticket and “establishment” Republicans, he sneers, “J.D. Vance Pick Represents Another Nail in Coffin of Reagan Republicanism.”

To which I say: J.D. Vance changed his mind on Donald Trump as the facts changed. It’s a pity that leading conservative voices like those on the Journal’s editorial board and those at National Review can’t bring themselves to do the same.

It’s a pity that they can’t get with the program and admit that the Republican Party is no longer theirs. And that it now belongs to Donald Trump. And that it’s embodied by the remarkable life story of a 39-year-old hillbilly from Appalachia.