President Joe Biden’s signature economic legislation isn’t dead. In fact, if Democratic Party leaders could only bring themselves to make a few hard choices, Build Back Better could even get better.

Momentum for the nearly $2 trillion bill has seemingly collapsed, with talks between Senator Joe Manchin and the White House breaking down and Senate Majority Leader Chuck Schumer’s self-imposed Christmas deadline looking impossible.

To see how to fix the bill, it’s necessary to understand how the current mess came to pass.

It all starts with the arcana of Senate procedure, in particular the budget reconciliation process. Most bills need 60 votes to pass, due to another bit of Senate arcana, but a budget reconciliation bill needs only 50 — which is exactly the size of the Senate Democratic caucus. (The bill would pass when the vice president breaks the tie.) So any Democrat who wants their legislative proposal to have a chance will try to include it in the reconciliation bill.

That helps explain why Build Back Better has always been a grab bag of progressive ideas rather than a thematically coherent piece of legislation. Democrats basically have one shot to legislate. So they started out with a giant $3.5 trillion bill that doled out goodies to every element of the party’s coalition.

They paid for it all with increased taxes on the wealthy, but moderates revolted at some of the revenue proposals, so the whole thing got cut down to $1.75 trillion.

That’s still a lot of money. But Democratic leaders didn’t want to disappoint anyone in their coalition. So the legislation they passed in the House is full of weird phase-ins and mid-decade expirations in order to limit the total cost.

Manchin regards these provisions as budget gimmicks, since his House colleagues clearly intend for the programs to be permanent.

The problem here is simple to describe, if not solve: Nobody in the party wants to make tough choices and tell some groups that they aren’t going to get what they want.

Start with child poverty. The Tax Cut and Jobs Act of 2017 increased the child tax credit from $1,000 to $2,000 per year and made some of its benefits available to the lowest income families — but also scheduled these enhancements to expire in 2025. Then this year’s American Rescue Plan boosted the credit (for one year) to $3,600 for children under 6 and $3,000 for kids between 7 and 17. It also made the tax credit fully refundable, so even families with no income could get the full benefit.

Progressives want to make this bigger child tax credit permanent, but that would cost about $1.6 trillion. So advocates like Senator Michael Bennet have been trying to sell Manchin on a one-year extension.

Then there’s the part of the legislation dealing with climate. In many ways the emotional and intellectual core of the bill is the $500 billion worth of investments in clean energy production and other climate-related issues. This is an issue Democrats care passionately about — and, remarkably, even Manchin is on board.

Adding this to the changes to the child tax credit, that leaves about $700 billion for Democrats to spend. They need to make some hard choices.

There’s no question that even a Manchin-sized version of Build Back Better would be a pretty big deal.

Matthew Yglesias is a columnist for Bloomberg Opinion and writes the Slow Boring blog and newsletter. He is also a co-founder and former columnist for Vox.