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Nearly one week after President Joe Biden’s disastrous debate performance — and amid a torrent of disappointing polls, embarrassing media reports and new doubts about his capacities — serious conversations about Biden’s future on the Democratic ticket are underway.

They are happening in Washington and Delaware and countless places across the country, and increasingly not just in private. A Tuesday MSNBC interview with former House Speaker Nancy Pelosi (D-Calif.), in which she said Biden needs to demonstrate whether the debate performance was indicative of a broader “condition,” felt like a turning point ― a signal, intentional or otherwise, that it’s OK for other Democrats to share publicly their anxieties about Biden’s ability to beat former President Donald Trump in November. (My HuffPost colleagues can bring you up to date on the Democratic panic here.)

Reports suggest Biden hopes to prove he’s up to the job, starting with a Friday sit-down interview on ABC News with George Stephanopoulos. Maybe he will succeed. Maybe he won’t. Either way, conversation has already started about what happens if Biden steps aside. And that has put the focus on Vice President Kamala Harris.

Harris is the most likely to take Biden’s place in almost any scenario, whether she receives some kind of formal endorsement from Biden and party leaders or simply has to prevail in an open contest for convention delegates. Among the plausible contenders, she has the most name recognition and stature. She, and only she, can say she’s been in the room and on the world stage with Biden, and performed under White House-level scrutiny.

She also has access to Biden-Harris campaign funds and infrastructure, which is a potentially big deal. Legally transferring either to another candidate would be difficult, as The American Prospect’s David Dayen has laid out.

The possibility of a Harris candidacy has actually been looming over Democratic Party politics for a while. Fear of it is one reason many Democrats were quick to shoot down the idea of Biden stepping aside earlier this year, when the main concerns were about his lagging poll numbers. The assumption has been that Harris would be a weaker alternative, as a candidate, a president, or both.

That assumption is rooted in beliefs that she’s an ineffective advocate and a poor manager of personnel, and that on a more fundamental level she lacks a clear sense of what she stands for or who she wants to be. The stories, quotes and observations from a pair of 2023 magazine profiles, one in The Atlantic and one in The New York Times Magazine, provided yet more grist for these worries.

But some of the perceptions of Harris date back to her failed 2020 Democratic primary campaign, and one moment in particular: her contribution to the debate over health care policy, which at the time was a major flash point. In that episode, you can see a politician with some of the very liabilities Harris’ critics perceive today. But you can also see one with strengths that many Democrats crave, especially in a president.

A Different Political Time

The debate actually took place in 2019, in the early, pre-primary part of the nomination battle ― and in a very different political environment.

It was nearly 10 years after enactment of the Affordable Care Act, aka Obamacare, and two years after Republicans had come within John McCain’s thumb of repealing it. The backlash to that effort, plus Democratic gains in the 2018 midterms, seemed to render the law politically safe. Within the party, debate circled back to where it had been in the 2016 primary fight between former Secretary of State Hillary Clinton and Sen. Bernie Sanders (I-Vt.) ― namely, whether to scrap existing health insurance arrangements in order to put everyone into a government-run “Medicare for All” system.

The idea itself dated back to the first serious efforts at universal health care, in the Roosevelt and Truman eras. During the Obama years, Democrats had settled on the public-private mishmash of the Affordable Care Act as a way to get past political obstacles that had stymied their efforts ever since. Because of the ACA’s complexities and gaps, millions of people still had no insurance, and millions more struggled with health care costs and insurance bureaucracies.

Medicare for All promised to address those problems, and found new political life in a party whose activists and intellectuals were already tilting in a more progressive direction. A big step forward came in 2017, when Sanders reintroduced his proposal and for the first time got significant backing from Democratic senators.

One of those senators, representing California, was Harris. When she kicked off her 2020 presidential bid, she signaled that she still supported the idea. But when it came time for her to roll out a detailed plan, it looked... different.

In a blog post and in material her campaign distributed to the media, she described it as “My Plan for Medicare for All.” But unlike the Sanders proposal, which he had turned into the cornerstone of his own 2020 bid, the Harris plan envisioned a lengthy, 10-year transition during which she’d subject the new, government-run insurance plan to “benchmarks” about access and affordability.

More importantly, her plan preserved a role for private insurers, which could continue to offer an alternative to public coverage in the same way they now offer a private alternative to Medicare.

Harris quickly drew fire from rivals on both sides. Officials from the Sanders campaign trashed the plan as “terrible policy” and “terrible politics.” Advisers to Biden, who had pointedly avoided endorsing Medicare for All in his own presidential campaign, warned that Harris’ approach would “unravel the hard-won Affordable Care Act that the Trump Administration is trying to undo.”

Harris made the situation worse in a CNN town hall, when she raised her hand to a question about which candidates wanted to abolish private insurance, something her proposal plainly did not do. She said afterward she thought the question was about her personal preference, not about which path forward on policy she favored. Whether or not this was true, it solidified impressions that she either didn’t know her own policy, wasn’t sure what she wanted, or both.

A Quest For A Middle Ground

Neither would be shocking, given Harris’ background as a prosecutor and attorney general who, as a fairly new senator in 2019, still had a lot to learn about domestic policy. The complexities of health care have tripped up even the wonkiest of politicians, including Sen. Elizabeth Warren (D-Mass.), who similarly stumbled and never recovered from her 2020 effort to put forward a variant of Medicare for All.

A common element in both Harris’ and Warren’s struggles was that the two senators, eager to differentiate themselves in a crowded field, were trying to find a middle ground somewhere between Sanders’ vision of wholesale transformation and Biden’s preference for more incremental change. That imperative led them to a political no-man’s-land, infuriating activists and partisans without inspiring supporters to push back.

But if Harris’ search for a compromise approach made for bad primary politics, it had a clear logic on the merits.

The kind of sweeping change Sanders envisions for health care would face enormous political challenges, not only because every industry group would fight it but because the majority of working-age Americans with employer-based coverage have been known to get nervous about proposals that jeopardize it.

And that’s to say nothing of the very real, very big mechanical challenges of trying to rewire one-sixth of the American economy. Among other things, the budget math of Medicare for All only works with significant regulation of doctor and hospital fees ― which, if imposed too hastily or crudely, could disrupt existing care arrangements.

Carrying such a proposal into the general election campaign would risk alienating swing voters; trying to get one through Congress would face low odds of success.

Among those who think the Harris proposal got a bad rap is Alex Lawson, the executive director of Social Security Works, who has a lengthy record of promoting Medicare for All proposals in public ― and of helping to craft proposals in private.

“It was good policy,” Lawson told HuffPost. “And regardless of how it played, or what lane she was in, you could see her motivations. She was actually working to fight for the American people, to lower costs, to take on corporate power in the health space especially. That’s real.”

Anthony Wright, incoming director of the national health care advocacy group FamiliesUSA, had a similar impression of the Harris plan. “I think it was an honest attempt to get to universality within the political and procedural constraints that exist,” he said.

Wright comes to FamiliesUSA from Health Access California ― where, as its longtime director, he had an up-close view of Harris even before she was a national figure. He told HuffPost that Harris used her time as California’s attorney general to make sure nonprofit hospital systems were living up to commitments for community service, and to launch the antitrust investigation of Sutter Health that led, eventually, to a $575 million settlement.

But mostly, the episode he remembered was right after Trump’s election, when Obamacare repeal suddenly seemed possible and Health Access organized one of the first ― quite possibly the first ― national rally to protect the law. Harris, then a senator-elect, was its first speaker.

“At the moment when we needed our elected leaders to be very loud and very clear about protecting the Affordable Care Act,” Wright said, “she was out there literally pre-day one.”

How much any of this matters, relative to other data points about Harris, is a separate and ultimately subjective question. But it’s worth remembering that a lot has changed in five years, and that includes Harris herself.

She’s famously fond of saying that “we have the ability to see what can be, unburdened by what has been.” Her 2020 foray on health policy is a reminder that sometimes even the recollections of “what has been” can be a little misleading.