It was just over five years ago — while Bernie Sanders was crisscrossing America’s early primary states, packing large arenas with throngs cheering his plans for free college, government child care and taxing Wall Street billionaires — when panicked politicos started openly attacking the Vermont senator as a dangerous socialist with ideas that bordered on un-American.

But the attackers were all Democrats.

“Here in the heartland, we like our politicians in the mainstream, and he is not — he’s a socialist,” then-Gov. Jay Nixon of Missouri told the New York Times in January 2016. His fellow Missourian, then-Sen. Claire McCaskill, said Republicans were salivating at the idea of facing Sanders instead of Hillary Clinton that fall, because “they can’t wait to run an ad with a hammer and sickle.” Tennessee Rep. Steve Cohen said nominating this democratic socialist “wouldn’t be helpful outside Vermont, Massachusetts, Berkeley, Palo Alto and Ann Arbor.”

Flash forward to 2021, and America’s gray-haired, 70-something new Democratic president — after beating Donald Trump in battleground states that Clinton lost in 2016 — is on Capitol Hill pushing a $6 trillion spending plan ($1.9 trillion already on the books, more than $4 trillion to go) that would have had those massive rally crowds in Boston or Ann Arbor dancing in the aisles. Large government stimulus checks. Money for families raising children. Free community college. A massive expansion of child care. A public works program of rebuilding roads and bridges. Much of it paid for by new taxes on corporations and the super-rich.

It’s hard to say what’s more unlikely about the most progressive White House agenda since Lyndon Johnson’s Great Society in the mid-1960s. That the Bernie Sanders presidency — well, maybe 75% of it — is on the brink of happening, or that it’s happening under a lifelong political pragmatist and centrist who’d spent most of his nearly 50-year career irritating left-wing Democrats, in the person of President Biden.

As the long, strange trip of the 46th president passed the 100-day mark last week, many progressive activists who started 2021 on a kind of red alert just waiting for Biden — after decades of clashing with the Delawarean over issues from mass incarceration to bankruptcy law — to govern as a milquetoast centrist found themselves instead writing unlikely love notes.

Consider the progressive journalist Mehdi Hasan, now a Peacock/MSNBC host, who in 2019 dismissed then-candidate Biden as “a 76-year-old white dude, with very few actual policies, in a party that’s been getting younger, more female and increasingly nonwhite in recent years,” on an Intercept podcast headlined: “Joe Biden Would Be a Disaster.” In recent weeks, Hasan has strongly praised the now-78-year-old POTUS, writing that his first days “look more like the fulfillment of a progressive wish list than a great centrist betrayal. Neither Bill Clinton nor Obama began their presidencies with such energy or ambition.” The left’s young political superstar, New York Rep. Alexandria Ocasio-Cortez, agreed, stating that — after expecting conservatism — “the Biden administration and President Biden have exceeded expectations that progressives had.”

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To be clear, those on the farthest left continue to find things to attack Biden on, and there are certainly ways that the Biden agenda is either different from — or, for a committed socialist, fall short of — that hypothetical Bernie Sanders presidency that we’ll never see. A President Sanders likely would have prioritized expanding health care more than Team Biden has, and would have gone after the Pentagon’s bloated spending, which the real POTUS 46 has disappointingly avoided so far. But up until now, the progressive wins have far outweighed these warts.

Meanwhile, Republicans are branding Biden’s $6 trillion program as “socialist,” just as they would have if Sanders had been elected in 2016 or 2020 — and just as they would have done if the president would have been Mike Bloomberg or Sen. Amy Klobuchar or some other Democrat who would have actually governed from the center. But it’s not sticking. In a time when Americans are more politically divided than any moment since the 1960s, Biden polls at 52% approval, or even higher, and his proposals for COVID-19 or infrastructure are much more popular than that. The “hammer and sickle” that McCaskill envisioned for Bernie would look ridiculous attached to America’s “Uncle Joe,” and to the public perception of Biden as reasonable.

But how did it happen that a career politician who palled around with segregationists and sought to tamp school busing in the ‘70s, promoted mass-incarceration policies in the ‘90s and flaked for Delaware’s credit card villains in the ‘00s has started to chisel his profile next to FDR and LBJ on the Mount Rushmore of left-wing domestic policy. Arguably, it took a perfect storm of “how” and “why” factors to get this unexpected presidency:

The American Cincinnatus. It took a bona fide national crisis — specifically, the road to Jan. 6 that Biden witnessed beginning in Charlottesville — to get a mid-70s politician still reeling from a family tragedy to come out of retirement. Biden’s late-life return to public service has more resembled the Roman legend of a civic-minded Cincinnatus than the White House sagas of ambition or ideology that Americans are used to. And this sense of mission — that Biden’s four years aim to end the crisis, not set the stage for reelection in 2024 — arguably prepared him for 2020′s unexpected plot twist.

The shock doctrine of ‘disaster socialism.’ COVID-19 wasn’t the crisis that Biden signed up for when he announced his candidacy on Philadelphia’s Ben Franklin Parkway nearly two years ago, but his new mental attitude of taking bold action — or risk watching the American Experiment implode — has led him to embrace what I’ve called “disaster socialism.” The popularity of 2020′s shock interventions — like stimulus checks and extended unemployment — and their role in averting Great Depression II has convinced Team Biden that America is ready for, and needs, an active government.

Only Biden can go to Norway. The wonderful phrase “only Nixon can go to China” (with its bizarre origin story) explains the political phenomenon that a politician with a long history of sober consistency on an important issue is best equipped to convince Americans when it’s time for a radical shift in direction. Thus, only a committed Communism fighter like Richard Nixon could open the door to Mao’s People’s Republic of China, and only Biden — with his reputation as a middle-of-the-road guy — could convince a majority of Americans that policies resembling Scandinavian-style socialism are needed in the present crisis. A President Sanders, with his avowed socialism and past comments on Nicaragua, the Soviet Union, etc., would have been beaten down, along with his proposals.

Sometimes you actually need a politician. Only a true career politician — in the best and worst senses of the word — could survive from 1972 through 2021 without once having been voted out of office. In gauging and reacting to the electorate rather than imposing his ego like a rigid ideologue — or a failed real estate developer — would do, Biden has shown a remarkable knack for evolution. That’s how a traditional, Mass-going Catholic politician became a leader on gay marriage when other Democrats still ran from the issue. And it’s how he’s adapted to the youth-driven leftward shift in Democratic politics, turning potential adversaries like Sen. Elizabeth Warren, AOC and, yes, Bernie, into mostly allies.

Watching Biden’s first 100 days, I’ve been most impressed by his ability to admit mistakes, quickly change course and try to do the right thing — not just on the big picture stuff but on the more immediate day-to-day crises. A series of events at the U.S.-Mexico border — some of them driven by Trump’s horrendous policies and the bad people in the U.S. Border Patrol who carry them out — caused a surge of young refugees in detention; while the primed Biden critics on the right but also on the far left railed about “kids in cages,” Team Biden quietly went to work, reducing the number of youth detainees by 84% in one month. Likewise, the initial bluster of an “America First” approach on global vaccine cooperation gave way to a generous deal with India.

Trust me, a piece like this is difficult to write, because a newspaper columnist is equipped with a default setting of cynicism. I have criticized Biden several times during these 100 days, although on most of these issues (refugees, vaccines, ending the ‘forever war’) he’s moved in a positive direction right after I hit the “send” button. I’ll still press the president to do more on shrinking the Pentagon or ending our racist way of policing than he seems naturally inclined to do.

But in March of 2016, I told readers of my then-blog Attytood that I planned to vote that year for “the only candidate who understands that health care and advanced education aren’t just a necessity in the 21st century but a basic human right, and the only candidate who’s made it this far without kowtowing to the billionaire donor class and the hedge fund interests on Wall Street. On April 26, I am going to vote for Vermont Sen. Bernie Sanders as if my life depended on it. It’s just that important.” I never imagined that I’d live to see the presidency I wanted — in the person of Joe Biden.

I’m also delighted that Bernie Sanders himself didn’t just live to see it, but that as chairman of the Senate Finance Committee he’s playing a key role in turning some of the ideas that he’s championed for decades into a hard-won reality. A lot can happen and possibly go wrong (cough, cough ... Joe Manchin) in the next few months, but I believe Bernie Sanders will be remembered as a pivotal figure in American history ... right alongside the politician who had the skill and the backstory to make many of his ideas happen: Joe Biden.

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