Last night’s Democratic debate exposed the contradictions within the party more vividly than anything yet this campaign season. On one side were Bernie Sanders and Elizabeth Warren, defending expansive redistributive policies like Medicare for All, a Green New Deal, and a wealth tax on the richest Americans. On the other side were indistinguishable centrist ciphers, responding with a steady mantra of “No, we can’t.”

But despite the best efforts of the moderators to prop up these bloodless mediocrities, Warren and Sanders could not be stopped. It’s now abundantly clear where the energy and dynamism in the Demoratic Party is. It’s with the Left.

The night started out with an extended section on health-care policy. This set the stage for the rest of the night, as it quickly became obvious that it was Bernie and Liz against the world. The moderators recycled tired talking points against Medicare for All, hammering again and again that it would “raise middle-class taxes,” as if the electorate has some bizarre preference for giving their money to insurance companies rather than the government. John Delaney responded with what the centrists clearly believed to be their trump card — that Medicare for All would take away union health-care benefits.

Yet the fact that this is what centrists fell back on reveals just how weak their position is. Union density in the United States is just above 10 percent. The vast majority of the US workforce does not have a union health plan. The Republicans have had no small amount of success in the last decade stirring up resentment against well-compensated union workers. But Delaney and company seem to think that trumpeting the privileges union workers have while fighting against the expansion of those privileges to the rest of the workforce is the route to electability. Though people might not have heard of Delaney before the debate, by the end, few had any questions as to why he is struggling to crack 2 percent in the polls.

Sanders and Warren were merciless in their responses to this kind of disingenuousness. Warren pointed out, quite correctly, that scaremongering about taking people’s insurance away is a Republican talking point. Sanders went for the jugular. When Delaney bragged about having been a health-care executive, Sanders snapped, “Maybe you did that and made money off of health care, but our job is to run a nonprofit health-care system.” And after the umpteenth ridiculous question about taxes from the moderators, Sanders reminded the audience that “[the health-care industry] will be advertising [during the debate] with that talking point.”

The battles over health care were unquestionably the most interesting part of the night, as it’s the area where the ideological differences between the candidates stand out the most. On immigration, or gun control, the differences aren’t nearly as stark. Nonetheless, the moderators did their best to gin up conflict — quoting one candidate’s generic declaration that their competitors weren’t doing x, and then asking a different candidate if, in fact, it’s true that they weren’t doing x. It was a nakedly artificial attempt to stir up squabbles, and one that quickly grew grating.

But it also exposed something important about the debates. The debates, after all, are not run by the Democratic Party. They are put on by CNN. And CNN’s main concern is not generating the most substantive back-and-forth, or trying to ensure that the best candidate rises to the top. Its concern is maximizing ad revenue by pulling in as many viewers as possible. This, ultimately, is why viewers were treated to reality TV–style tricks to stoke conflict. And why a nonentity like John Delaney was gifted with speaking time and again — because the producers knew his dour centrism was the key to creating conflict onstage.

The Democratic Party remains a thoroughly corporate vehicle, one happy to outsource the process of selecting candidates to giant media corporations. Yet inside that media spectacle, it’s impossible to deny that the energy is with the left in the party. Sanders and Warren carried the night with their energy and ambition, while centrists like Delaney or John Hickenlooper were left trying to rouse enthusiasm for their infrastructure plans. Candidates attempting to seize the non-ideological lane, like Pete Buttigieg or Beto O’Rourke, looked like they showed up to the wrong event.

After last night, the conclusion is inescapable: the Left is winning.