Last month, the Democratic Congressional Campaign Committee (DCCC) introduced new rules intended to stymie electoral challenges from the left. The group announced that it would no longer give any work to consultants, pollsters, and other political professionals who lend their efforts to progressives and democratic socialist candidates seeking to depose Democratic Party incumbents, as Alexandria Ocasio-Cortez did last summer when she unseated establishment Democrat Joe Crowley.

Members of the Congressional Progressive Caucus, including Ocasio-Cortez, are right to speak out against these measures, which are designed to weaken the Left. Since the left wing is already weaker, forcing professionals to choose between the Left and center means they’re likely to gravitate to the center to protect their own careers, starving the left wing of resources and expertise. The move is an attempt to leverage the self-interest of the professional political class against a political movement that threatens corporate profits and centrist dominance, which are extensively entangled.

One wonders, given the extreme resistance to the Left from the Democratic Party establishment, why progressives and democratic socialists should run as Democrats at all. Unfortunately, the unique characteristics of the US two-party system make it nearly impossible in many cases to run viable and impactful third-party campaigns. That means that in order to widely project a pro–working class message while still potentially winning a race, many progressive and democratic socialist candidates are compelled, for the time being, to run on the Democratic Party ballot line — that is, to run as putative members of a party that detests them.

The ballot-line approach presents two clear and present dangers: stonewalling by the party elite and cooptation into the party machinery. The Democratic Party knows its way around both. In this instance, likely acting out of sheer panic, it has opted for stonewalling.

But stonewalling has some advantages over cooptation for insurgent candidates genuinely interested in creating a new working-class political movement in defiance of the Democratic corporate consensus. If they won’t give you anything, you don’t owe them anything. By making it clear that the party won’t provide resources to the Left, Democrats force progressives and democratic socialists into a position of independence. That may make it somewhat harder to win elections, but in the long run, relative independence will serve the movement well — so long as it can sustain its popular momentum.

In fact, forced independence might actually compel progressive and left-wing candidates to adopt the very strategies that are necessary to build and sustain a mass base. If you can’t rely on a readymade political machine, you need to build a machine of your own. Instead of sharing the political professional class with its opponents in the Democratic Party, the Left will need to build its own army of experts and operators — an army that, once assembled and trained, can be deployed to other blacklisted campaigns.

By the same token, if you don’t have access to a network of elite donors, you need to find new ways of speaking to ordinary people that inspire them to fork over their hard-earned money. If you’re not getting fed, you don’t have to worry about biting the hand that feeds you. You can, and indeed must, stand for an ambitious politics that can get working people’s attention by promising to radically transform their lives: for Medicare for All, fully funded public childcare and education at all levels, a Green New Deal, massive social housing investment, a job guarantee with a living wage, and soaking the rich to pay for it all and redistribute our nation’s obscenely concentrated wealth.

Cutting off the Left therefore has the potential to backfire on the center, pushing candidates to be more courageously independent in order to win the hearts of the masses — the only way to make up for what they lack in top-down support. And in the process of running those audacious insurgent campaigns, progressive and democratic socialist politicians can raise the expectations of the working class and create new constituencies for policies and politics that the Democratic center dismisses out of hand.

Emboldening-by-abandonment is much more promising for the growth of a left mass movement than the alternative scenario — where Democrats play nice with the Left in an attempt to co-opt its leaders and neutralize its political threat. The DCCC’s scorched-earth tactics have a silver lining: if political consultants are forced to reject insurgent campaigns, they can’t remake insurgent campaigns in their image.

This isn’t to say that cooptation is entirely avoidable. The Democratic Party is not a political party in the traditional sense, with members and internal democracy and a mandate to answer to the needs and desires of its constituency; it’s a Rube Goldberg machine made out of carrots and sticks. Progressive and democratic socialist politicians who win elections as Democrats are likely to be subjected to a litany of bribes and punishments, which take enormous effort to resist. Newcomers like Ocasio-Cortez, Rashida Tlaib, and Ilhan Omar are at the very beginning of this long and arduous journey, and despite their personal integrity and their antagonism to the party establishment, their fates cannot be predicted.

Their best shot at surviving the gauntlet is if the movement on the ground continues to grow in both size and political clarity. There’s a real hunger among the American working class for change — for an end to stagnating wages, rising living costs, ballooning debt, and crushing austerity. And as the unexpected success of Bernie Sanders’s dark-horse campaign showed in 2016, there exists a potential constituency for a mass left-wing movement.

The formal parliamentary expression of that constituency is not a foregone conclusion — progressives and democratic socialists will have to work tirelessly to build the movement into a real threat to establishment power. But alarming signs of its strength and coherence are precisely what have prompted the Democratic Party to act with such aggression.

The DCCC has drawn its sword. But it mistakes the left-wing insurgency for a snake, when it may be a hydra instead.