If President Donald Trump is defeated, the GOP is going to want to work with Democrats again, making an ambitious agenda possible. That, at least, is former Vice President Joe Biden’s theory of the case. “You will see an epiphany occur among many of my Republican friends,” he said in November. “Mark my words.”

Biden was mocked for these comments, and rightly so. There will be no Republican epiphany if Biden is elected, just as the fever didn’t break when Barack Obama was reelected. Biden came of political age in the Senate of the 1970s and ’80s, when the political parties were ideologically mixed and bipartisanship was common. He yearns for a political structure that no longer exists and hasn’t for some time.

But Biden isn’t alone in running on an unlikely theory of change. Sens. Bernie Sanders and Elizabeth Warren, and former South Bend, Indiana, Mayor Pete Buttigieg are all running on a theory in which the force of their personality, or the strength of their movement, or the popularity of their agenda breaks the polarization that has gridlocked US politics.

But why is it that every presidential candidate needs a fantastical step between being elected president and turning their promises into policy? In many countries, this whole conversation would be puzzling. Parties run on agendas, and if they win, they implement those agendas, or at least a substantial part of them.

That’s not the case in America, where divided government is common, the filibuster forces supermajority levels of consensus in the Senate, electoral geography dilutes the power of popular majorities, and polarized parties make compromise impossible. Here, parties run on ambitious agendas and, when they win, typically find themselves foiled in their efforts to pass much of anything at all. Elections then devolve into bitter games of blame-shifting, in which the question isn’t how the public feels about what did happen but who the public holds responsible for what didn’t happen.

“There is a chasm between expectations and reality,” says Paul Pierson, a political scientist at UC Berkeley. “Many voters don’t know who controls the Senate, much less the role of the filibuster. Trump can talk about the ‘do-nothing Democrats’ while House bills gather dust in a corner of McConnell’s office! Voters are completely uninterested in process explanations. They don’t want to hear about how candidates can’t actually do things.”

Frances Lee, a political scientist at the University of Maryland, agrees. “Realism about these constraints is just not a compelling electoral message — neither for primary voters nor the general election. How are you going to tell activists that little legislation of any kind is going to get done without bipartisan support? How can you get voters to care about the outcome of an election if you’re telling them that even if you win, the opposing party will have a veto over most of the things they care about?”

You can’t. And successful politicians don’t. Epiphany politics is how candidates close the rhetorical gap between what the public wants to hear and what the president can actually do. But it doesn’t close the real gap between what the president can do and what the public wants done.

Epiphany politics are everywhere

At CNN’s recent town hall, Bernie Sanders was asked how he’d win the Republican votes in the Senate necessary to pass his agenda. “You go to Mitch McConnell’s state of Kentucky, which is a state where a lot of people are struggling, and you say to those people, ‘Okay, this is my proposal,’” Sanders replied. “We’re going to lower the age of Medicare from 65 to 55, and we’re expanding it to cover, as I mentioned, dental care and home health care and eyeglasses and hearing aids.

“What percentage of the people do you think in Kentucky would support that proposal? My guess is 70 percent, 80 percent of the people. And my job then as president is to rally those people and tell their senators to support it. I think we can do that.”

But there is no more evidence that Sanders can enlist Mitch McConnell’s voters than that Biden can coax an epiphany out of McConnell.

When deep blue Vermont sought to pass single-payer health care in 2014, the plan failed despite Sanders’s personal popularity in the state, a supportive Democratic governor, and big Democratic majorities in the legislature. Meanwhile, Sanders has had trouble convincing even his fellow Senate Democrats to sign on to his legislation. At Friday’s Democratic debate, Sen. Amy Klobuchar (D-MN) dismissed Medicare-for-all as a legislative fantasy. “It is not real, Bernie, because two-thirds of the Democrats in the Senate are not on your bill and because it would kick 149 million Americans off their current health insurance in four years,” she said.

The Iowa caucuses, similarly, offered little evidence for the kind of political revolution necessary to intimidate Republican members of Congress into supporting democratic socialism. Iowans know Sanders well; he’s spent a tremendous amount of time and money selling them on his politics, and his team has spent years organizing up and down the state. Even so, though caucus turnout was higher than in 2016, it was far lower than in 2008, and the result was that Sanders and Buttigieg basically tied. There’s nothing in that outcome that suggests Sanders can change the political dynamics of Kentucky.

Warren and Buttigieg have their own version of epiphany politics: ambitious plans to make American governance possible again by getting rid of the filibuster and passing a sweeping set of political reforms ranging from anti-corruption legislation to statehood for Washington, DC, and Puerto Rico to reshaping the Supreme Court to abolishing gerrymandering and the Electoral College.

This strategy also requires an epiphany — in this case, from Senate Democrats, most of whom oppose getting rid of the filibuster because they fear someday being in the minority without it. Minority Leader Chuck Schumer has said he regrets even the modest changes Democrats made to the rule in 2013.

Schumer isn’t alone in this. A majority of the Senate Democrats who ran or are running for president in 2020 — Booker, Klobuchar, Bennet, Harris, and even Sanders — either support the filibuster outright or hedge when asked. But so long as the filibuster remains in place, the rest of any political reform agenda is so much legislative vaporware.

All this has left outside analysts skeptical that any Democrat will bring much in the way of dramatic change. In a recent note to investors, JPMorgan told restive traders not to fret over the Democrats’ ambitious agendas, putting the probability of the conditions necessary for single-payer or a wealth tax to pass “at less than 5%.”

The purpose of epiphany politics

Presidential campaigns are defined by a central question — how will you get all this done? — to which there is, in truth, no good answer.

Since most presidents fail to pass anything close to the program they run on, would-be successors need an answer for why their presidency will be different. Running on a realistic view of what’s possible doesn’t excite the base or match the scale of our problems — just ask Klobuchar, who’s offered the closest thing to a plausible agenda and has been lapped by candidates with more inspiring platforms.

“Candidates have to tell a story where things will be different next time,” says Lee. “Their epiphany stories may not be very persuasive, but the unvarnished truth is almost certainly worse from an electioneering perspective.”

The downside of epiphany politics is that it sets up both a candidate’s supporters and the country for disappointment. Former President Obama is personally beloved by Democrats, and passed more and more consequential domestic legislation than any president since Lyndon Johnson. But it was a fraction of what he promised, and the bills that did pass were shot through with compromises and concessions.

Arguments rage to this day among liberals about why Obama wasn’t able to pass a bigger stimulus, force through a public option, find the votes for cap and trade, reform the immigration system, and get Merrick Garland onto the Supreme Court. He promised hope and change, but not enough changed, and that robbed the activists he inspired of hope.

Trump signed a big package of tax cuts into law, but his wall remains unbuilt, Obamacare is the law of the land, the opioid crisis is ravaging the Midwest, and the grand rebuilding of American infrastructure has been left to future presidents. Trump inherited and sustained a strong economy, and he’s performed a dramatic presidency through Twitter fights, scandal, and erratic behavior, but he’s been a legislative failure.

The gridlock at the center of the system resists efforts at political reform as easily as it resists the bills political reform is meant to enable. But that traps both parties in an endless cycle of epiphanic hopes and deep disappointments — so the frustration with failed political insiders gives way to a demand for political outsiders, and the failure of those outsiders creates demand for reactionaries and revolutionaries.

But what happens if they fail, too?

Epiphany politics delays a reckoning. It promises people the change they want, but it can’t deliver it. And so the public becomes more frustrated, the politics more bitter, and both sides more desperate. Here, then, is the epiphany we need: What American politics lacks isn’t good candidates but a functional political system. And so long as that problem goes unfixed, no candidate, in the end, will be good enough.

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