Basically, it's a one way street, and in order for the democratic wing of the Democratic Party fix the party, the corporatists need to experience the consequences of bad faith behavior:
The question of how hostile the left should be to the Democratic Party is as old as the hills, but it becomes especially acute when the Republicans are in power: after all, with so many harmful policies for working-class and minority communities coming down the pike, isn’t it best for the left and the Democrats to join arms against a common enemy rather than engage in a “circular firing squad”? That argument played out in the pages of Dissent this week: in a response to Gabriel Winant’s excellent piece on the new working class, which was highly critical of the Democrats, Dissent editor and left historian Michael Kazin writes a plea for left unity with the Democratic Party:If one looks at the history of the Democratic Party over the past few years, this whole "New Democrat" thing has been a disaster, both electorally and in terms of policy.
For now, it’s crucial that leftists not spend their energy attacking mainstream Democrats, either present or past, as hopeless “neoliberal” sellouts. It is hard enough to defeat the odious plans that Trump and the Republican Congress want to impose on the nation. If we are engaged in a furious internal battle, it may become impossible. Instead, we should emulate Keith Ellison and Bernie Sanders—who have played down their differences with the likes of Tom Perez and Chuck Schumer—and train our fire at the enemy without and not at vital, if not always reliable, Democratic allies.
Kazin recites a perspective one hears often, particularly in the wake of the intensely divisive 2016 primary—mainly from the Democratic center but also from those on the left, like Kazin, who believe that resisting Trump, rather than settling internecine ideological scores, should be our main focus.
For a contrasting view on the subject of party unity, we need only look to the example of a prominent Democratic politician by the name of Barack Obama. In the aftermath of an extraordinarily fractious primary campaign that left the Democrats deeply divided between Clinton and Sanders supporters, the Sanders side recruited Keith Ellison to run for DNC chair. Ellison looked poised to cruise to an easy victory; for Obama to support him or at least stand aside would have been a powerful symbolic affirmation that whatever had happened during the primaries, Democrats now stood united in opposition to the Republican agenda.
So naturally Obama immediately recruited a challenger to Ellison from the ranks of his own administration and pressured the DNC electors to quash the Ellison candidacy, thus affirming his own faction’s control of the party machinery at the cost of party unity at a historical nadir of the Democrats’ power.
What did Obama understand that Kazin didn’t? He understood that party unity is a story for rubes. It’s a feel-good line for pundits and a convenient thing for the rank-and-file to believe, but not something practical politicians take seriously.
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Doesn’t this permanent internecine warfare render a party ineffective against its opponents? To answer that question one need only look to the Republicans. The Republican Party is an ideologically diverse coalition incorporating ethnonationalist populists, billionaire libertarians and family-values evangelical conservatives, and since the advent of the Tea Party its factional strife has been far deeper and more intense than the Democrats’. The Koch network and the Tea Party movement have been conducting what amounts to an incredibly well-financed all-out civil war with the Republican establishment, doing things like primarying Eric Cantor, felling John Boehner and forcing Republican Congressional leadership to drive the nation to the brink of default. (Imagine if the Sanders wing of the Democrats successfully primaried Nancy Pelosi or shut down the government over single-payer.) Yet if this has hurt the GOP electorally, it’s hard to see how; in the same timespan that this civil war has intensified, the Republicans have achieved a level of electoral dominance over their Democratic opponents not seen in a century.
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Kazin may well prefer a centrist Democratic administration to a Republican one—I certainly do—but that’s not the choice we’re faced with now. Allowing the centrists to run things unopposed is what got us here. Only the progressive left offers a way forward in the fight against Trump, because only the progressive left can build the coalition to beat him—but to do so we’ll need to reshape the Democratic Party, which means seeing off those who control it now. Fighting the Clinton-Obama wing of the Democratic Party isn’t a distraction from beating the GOP: it’s a vital first step.
To quote Harry S Truman, "Given the choice between a Republican and someone who acts like a Republican, people will vote for the real Republican."