Representative Alexandria Ocasio-Cortez walked into Thursday’s meeting between House members and President Joe Biden with precisely the skepticism that the moment required. As the president prepared to outline another “framework” for a scaled-down domestic agenda, the progressive Democratic representative from New York said, “We need certainty.”

“I think legislative text is one mechanism of us getting there. I think we’re open to other mechanisms,” Ocasio-Cortez told reporters. “But it needs to be something a little bit more than a back of an envelope.”

She is precisely right.

Progressives cannot back off on their demand that the details of a downsized “Build Back Better” social infrastructure bill be confirmed and endorsed by all the Democrats in the Senate before the House approves the bipartisan $1.2 trillion physical infrastructure plan that is the top priority of corporate-friendly “centrists” in Congress. Without precise text describing what is in the plan, and without a clear commitment from Senators Joe Manchin (D-W. Va.) and Kyrsten Sinema (D-Ariz.), members of the Congressional Progressive Caucus have to hold firm.

Caucus chair Pramila Jayapal (D-Wash.) is spot-on when she says that members need to know what’s contained in the president’s framework before the House acts. “We want to see the actual text because we don’t want any confusion or misunderstandings,” Jayapal told reporters. Representative Cori Bush (D-Mo.) reaffirmed that point when she said she is holding out for both details and a clear signal from a united Senate Democratic Caucus. “I need to see text, but I want a Senate vote,” she said. “Right now that’s still where I stand.”

Bush has got the backing of Senate Budget Committee chair Bernie Sanders (I-Vt.), who said to reporters, “I think before there is a vote in the House on the infrastructure bill, the members of the House have a right to know that 50 US senators are supporting a strong reconciliation bill.”

Negotiations are not done. In fact, they are at a critical stage. Activists understand this. They are not calling for a rejection of Biden’s plan; they are calling for clarity. “Over the last year, progressives in Congress have played a crucial role keeping the Build Back Better Act on track, even in the face of a multi-million dollar lobbying campaign by big business to kill it in its cradle,” declared a letter issued Thursday morning by dozens of groups, including the Working Families Party, Justice Democrats, Greenpeace USA, the National Organization for Women, Our Revolution, People’s Action, and Social Security Works. “Now we’re in the home stretch. By holding firm on keeping the Build Back Better Act and the Bipartisan Infrastructure Bill firmly linked, progressives are giving their colleagues in the Senate the space and the leverage to negotiate the strongest package possible.”

More than a decade ago, in the early stages of Barack Obama’s presidency, progressives were repeatedly told that they had to compromise and accept a less ambitious response to the Great Recession than Obama had proposed and that most Democrats wanted. Ultimately, they settled for a smaller package because they were told it was necessary to act quickly. But the quick action proved insufficient and uninspiring to voters the following election. In 2010, Democrats lost control of the House and had to govern in a severely limited capacity. Former Presidents Bill Clinton and Jimmy Carter suffered their own midterm setbacks after pulling punches in the first years of their first terms.

So holding out for the best possible package is not merely a morally sound approach. It’s a politically necessary one.

Insider politicians and pundits may try to suggest that the progressives are obstructing action by demanding details from Biden and commitments from wavering Senate Democrats. But that’s absurd.

Progressives have compromised again and again during this process. They did not demand that a newly elected Democratic president establish a Medicare For All program, implement a Green New Deal, or tax billionaires out of existence through the reconciliation process. They backed off their initial proposal for a $6 trillion plan to begin to address scorching inequality in the United States, along with a climate crisis and the challenges of transitioning to a 21st-century economy. They settled for a $3.5 trillion plan that Biden and Democratic leaders in the House and Senate assured them was doable. They agreed to strategies for passing the bipartisan infrastructure plan, in combination with the $3.5 trillion reconciliation bill, which would fund Medicare expansion, care for the elderly and people with disabilities, paid family and medical leave, expanded tax credits to alleviate child poverty, free community college, and a robust response to the threat of environmental catastrophe.

Progressives negotiated in good faith as Senators Manchin and Sinema abandoned past commitments and began a steady process of diminishing expectations and downsizing goals. The Clean Electricity Performance Program, a key climate initiative that would use a combination of incentives and mandates to get utilities to embrace renewable energy, was jettisoned to appease the coal baron from West Virginia. A proposal to reduce prescription drug prices was dumbed down at the behest of Sinema, Big Pharma’s new favorite senator. Paid family and medical leave is apparently gone. So too are hugely popular proposals to expand Medicare coverage to include vision and dental care.

The ambitious $3.5 trillion plan of late summer has withered to a $1.75 trillion proposal. It is still expected to include many commendable initiatives: free and universal preschool for all 3- and 4-year-olds, expanded Medicaid coverage for home care services for seniors and people with disabilities, an enhanced child tax credit to fight poverty, $150 billion for affordable housing, a surtax on billionaires, and a minimum tax for corporations. It may be worthy of passage. But even Biden reportedly acknowledged to House members when he met with them briefly on Thursday morning that not all the pieces are in place. And Senate majority whip Dick Durbin (D-Ill.), asked if all Democratic senators were on board, said, “I wish I could say yes, but there’s a great deal of uncertainty within the caucus as to what’s contained in the deal. I will tell you there is a will to do it.”

That is not a sufficient assurance that this framework will support the programs that are necessary and extraordinarily popular with the American people.

A month ago today, Sanders said, “I strongly urge my House colleagues to vote against the bipartisan infrastructure bill until Congress passes a strong reconciliation bill.”

That’s still the best counsel for House progressives, and for Americans who sincerely want to build back better.