As we move closer to the 2018 primaries—a critical moment for Democrats attempting to put a dent in Donald Trump’s agenda—the two most prominent figures from the last primary have assumed very different roles.

Let’s start with Bernie Sanders. The importance of his insurgent campaign—a surprise challenge to Hillary Clinton at a time when she looked like the prohibitive favorite to win the nomination—has become increasingly evident as time passes. Unlike Clinton, his popularity has not suffered as a result of an electoral defeat—in fact, he’s currently the most popular politician in America, while Clinton’s approval metrics languish somewhere to the south of Trump. Sanders, who has become the de facto leader of the Democratic party even as a nominal “independent,” is set to introduce a Medicare-for-all bill to the Senate on Wednesday.

That’s not remarkable in and of itself—anybody can introduce legislation. What’s remarkable is who has signed on in support, a growing list that includes anybody with presidential ambitions in 2020. It’s not just Elizabeth Warren progressive types anymore. Kamala Harris, Cory Booker, and Kristen Gillibrand, all of whom are considered moderates, have signed onto Sanders’ bill. And they’ve done so publicly:

Health care is a right, not a privilege. This week, I'll proudly join Senator @BernieSanders to co-sponsor Medicare for All. — Kirsten Gillibrand (@SenGillibrand) September 12, 2017

Quality health care should be a right not dependent on wealth—that's why I'm cosponsoring the Medicare for All Act: https://t.co/6CgdrHPwZl — Cory Booker (@CoryBooker) September 11, 2017

I intend to co-sponsor the Medicare for All bill because it's just the right thing to do. — Kamala Harris (@KamalaHarris) August 30, 2017

The “Overton Window” is a term meant to define the range of acceptable discourse in a certain time and place. In Democratic American politics, circa early 2016, advocating for universal healthcare was not inside the Overton Window—in fact, it was considered a campaign killer. The fact that it's not only inside the window today, but that support for it has practically become a requisite for any ambitious Democrat, is entirely the doing of Sanders. His campaign shifted the ideological grounds, and has redefined the party's platform. We're rapidly approaching a point where failing to support the concept of universal healthcare will be a dealbreaker—at this point, 60 percent of Americans favor the idea, and that number is consistently growing with time. Even Max Baucus, the former Montana Senator who was instrumental in ensuring that Obamacare had no single-payer option, has come out in favor of the idea.

It's a simple, popular idea, but it took someone like Sanders with the courage to defy inherited political wisdom and bring it out from under the shadows of history and into the mainstream. It's not the only example, but it's the most prominent right now, and it helps explain why Sanders himself has maintained and grown his personal popularity in the Trump era. This phenomenon has little to do with Sanders in particular—he has authenticity on his side, but no special charisma. It's the strength of his ideas that have persisted and grown. Winning and losing isn't his primary concern, and his political beliefs are all aimed at the future. And as that future approaches, he's positioned himself as the most influential leader on the left.

Then there's Hillary Clinton, who remains firmly rooted in the past. She lost the general election to an enormously unpopular candidate, and nearly lost the primary to Bernie Sanders, because she couldn't rely on the strength of her ideas. Hers was a personality- and identity-based campaign rather than an ideological one, and it came with the underlying belief that Her Time Had Come. So it's no surprise that in the aftermath of an historical loss to Trump, her ego-centric rhetoric remains fatally attached to herself, and therefore attached to the past. (Worth noting: Between the future and the past, only one can be changed for the better.)

Clinton's new book, What Happened, is a post-mortem that looks for blame everywhere but the proverbial mirror. It is rife with complaints, but woefully short on honest self-analysis. (There's a comical comparison here to Sanders' own recently released book, which is a policy-based look at the future of progressivism.) There's plenty of aspersions to go around, but Bernie Sanders came in for special treatment:

Hillary Clinton does not hold back when she talks about Bernie Sanders in her new book pic.twitter.com/LdGs5a1ean — Edward Hardy (@EdwardTHardy) September 5, 2017

(Ironically, one of her most pointed criticisms—that Sanders’ policy beliefs are the equivalent of offering everyone a “pony,” and that she was the candidate of political realism—is directly undermined by the recent surge in support for universal healthcare.)

She continued her “looking back” tour this morning on NPR, and re-hashed all her complaints about Sanders:

I find this criticism from Sanders supporters to be so off base. He’s not even a Democrat. That’s not a slam on him. He says it himself. He didn’t support Democrats. He’s not supporting Democrats now. I know a lot of Democrats. I’ve been working on behalf of Democrats, to be elected, to be re-elected, for decades. And so yes, I was familiar to broad parts of the electorate, and I’m proud of that. And I did well across the country. I won by four million votes. That’s a landslide. I won, really, by March and April. But he just kept going, and he and his followers’ attacks on me kept getting more and more personal, despite him asking me not to attack him personally. And, you know, I really regret that. But now he’s got a chance to prove that he’s something other than a spoiler. And that is to help other Democrats. And I don’t know if he will or not, but I’m hoping he will.

As Clio Change at The New Republic comprehensively showed, most of this is either untrue or deeply hypocritical. More importantly, it begs the question: What is Hillary Clinton doing to help the party?

The answer is clear. While Sanders stands in the face of the Trump wave, a 76-year-old man fighting tooth and nail and with unprecedented success to bring healthcare to all Americans, Clinton has only emerged from hiding months later to promote a querulous book and sow further divisions on the left. Their respective actions in the wake of a horrifying election result have proved the point: Sanders cares about the future, while Clinton cares only about herself.