Their increased clout is a shift from the Obama years, which conditioned Democrats to expect the left to crumble under Biden during debates over Obamacare and the 2009 stimulus. “Some of our progressive values have become quite mainstream,” said Jared Huffman, a five-term Democrat from California. “I also think that sometimes in the past, our progressive community/caucus might have been treated as, or assumed to be, adversaries and outsiders and not had a seat at the table. And I think we’ve been treated as allies by the administration and by everyone else.”…

The situation in the Democratic caucus bears a resemblance to the arch-conservative House Freedom Caucus, which notoriously tried to drag every key bill to the right and fueled government shutdowns and debt-limit standoffs in the process, against the wishes of Republican leadership. “The knock on the Freedom Caucus is they know how to start a fight but not how to end one,” Matt Gaetz of Florida, a member of that group, told Intelligencer. “The current energy from progressives seems to suggest that they will end it, they will bring down the infrastructure bill if it doesn’t pave the way to their spending ambitions.”

The lessons from the right go both ways, according to Gaetz. “The progressives trying to get their way now have observed the flaws that the Freedom Caucus used to try to get their way on health care,” he said. “The Freedom Caucus fundamentally ended up empowering McCain in the end to kill [Obamacare repeal] and I don’t think progressives want to do that with Manchin and Sinema.”