The infrastructure deal struck late on Friday evening gave Biden a desperately needed win. It represents an opportunity to regain control of the political narrative that the Afghanistan debacle in August had stripped from his grasp. Since that time, his presidency has taken a series of damaging hits, culminating in the party’s dispiriting losses in Tuesday’s elections. The deal reached between the moderate and progressive wings of the Democratic party had to happen for the party to have any chance of keeping its congressional majorities in 2022.

The passage of the billion-dollar-plus infrastructure bill is the largest appropriation of its kind since the Eisenhower Congress gave America its interstate highway system in the 1950s. Infrastructural improvements in the country are urgently needed and, if handled well, will be greeted with enthusiasm by Democrats and Republicans alike. The size of this bill, in combination with Biden’s $1.9tn American Rescue Plan passed last spring, and the likelihood that some version of the social infrastructural bill will pass Congress before the end of the calendar year, puts Biden’s ambition in New Deal-second world war territory. It will quiet critics of the FDR-Biden comparisons, at least for a time.

The bill’s passage coincides with encouraging news on the economic and Covid-19 fronts: Friday’s jobs report was better than expected, the virulence of the Delta variant may have peaked, and Pfizer’s report of an effective treatment for those ill with the disease may turn out to have as much significance as the announcement a year ago that vaccines were on their way. Imagine if the Pfizer medicines, by election season 2022, turn Covid infections into nothing worse than a bad cold or the flu. Credit will fall to the Democrats.

Friday’s victory is also notable for delivering on Biden’s promise of bipartisanship. Thirteen Republican votes in the House of Representatives hardly constitute a wave but they represent 13 more than the total cast by Republicans for Obama’s Affordable Care Act in 2010. Those 13 yea votes, moreover, breached the rules governing Trump-style politics, which dictate giving opponents no quarter. Trump will not take kindly to hearing reports that “sleepy Joe” has succeeded on infrastructure where the Great Leader himself had failed. It may be that a movement out of the Trump era, if it is to happen, will occur through a series of modest steps rather than through one big bang.

It will take days and weeks for full reports of Friday’s tense negotiations to emerge. But already there are two details worth highlighting. First, Black politicians, this time in the form of the Congressional Black Caucus, came to Biden’s rescue much as Jim Clyburn had in the crucial South Carolina primary in February 2020. Nancy Pelosi helped this maneuver along by sending out Joyce Beatty, head of the Congressional Black Caucus, to deliver a message to the progressives that, at this critical moment, they needed to check their legislative utopianism at the door and vote for the infrastructure bill. Biden must take appropriate notice of this Black Caucus intervention, and find ways to reward it.

Second, Biden must also understand that the progressives compromised more than the moderates did. For months, the former had pledged to hold up the infrastructure bill until its fraternal twin, the social infrastructural bill known as the Build Back Better Act (BBBA), passed as well. The skillful Pramila Jayapal, head of the House’s Progressive Caucus, extracted the equivalent of sworn oaths from key party moderates to vote for BBBA when it comes up for a vote (as it will) sometime in November. But these moderates will have an escape hatch: If the Congressional Budget Office’s costing of BBBA turns out to be much higher than expected, they will claim that such a “worrisome” estimate relieves them of their solemn obligation to vote yea.

Biden and Pelosi cannot allow the moderates to wriggle free in this way. Progressives will regard this as a betrayal, and their willingness to contribute their essential energy and support to the Democrats in 2022 will ebb. Collaboration between progressives and moderates in the Democratic party has rarely been easy. But, historically, the party has made its greatest advances when the alliance has held. To sustain that alliance in this moment, both groups must come out of the current legislative season with a win.

Biden must now convert his Capitol Hill accomplishment into economic and technological achievements. He must use his bully pulpit to talk up the virtues of his infrastructure bill. He must demonstrate in concrete terms that work on multiple projects is under way via hiring commencing, diggers breaking ground, cranes sprouting across city skylines, and landscapes transforming. Biden should emulate the success of the New Dealers in using infrastructural initiatives to demonstrate to Americans of all kinds that the federal government was working on their behalf. He doesn’t have a lot of time. He’d help his cause by finding and unleashing his own Harry Hopkins, the irrepressible New Deal administrator who was brilliant at cutting through red tape and moving major infrastructural projects from blueprint to reality.

There will be challenges galore: completing environmental impact studies in a timely manner, pushing projects through the country’s balky federal system, honoring principles of diversity in issuing contracts while also overcoming labor shortages stemming from the “great resignation”, to name only a few. But this is also Biden’s opportunity to show that he, not Trump, is the man who knows how to make American great again. The passage of the infrastructure bill opens a path to victory in 2022.

• Gary Gerstle is Mellon Professor of American history at Cambridge and is writing The Rise and Fall of the Neoliberal Order (2022). He is a Guardian US columnist.