On Thursday evening, mere hours before the Senate is supposed to vote on a health care bill, the United States Capitol is in chaos.

This is what we actually know:

Senate Republicans have still not released the actual text of whatever they will vote on at the end of their debate, probably Friday morning.

Many Republican senators don’t want their bill, whatever it is, to actually become law. But they might still vote for it, because they want to pass some bill, any bill, and then open up negotiations with the House on a bigger health care package.

There are rampant if unverifiable rumors that House Republicans are prepared to pass whatever the Senate sends them, perhaps as soon as Friday,

Some senators are threatening not to vote for their own health care bill unless House Republicans assure them that they will not pass the Senate bill.

The real story is that Republicans, after seven years of promising to repeal and replace Obamacare, are unable to come up with a plan to actually do that, and it has come crashing down on them at the finish line. The Senate is hours away from voting on a bill, without knowing what it is or whether it could become federal law in a matter of hours.

One congressional staffer sent me an email with the subject line: “This is insane.”

The House and the Senate are now locked in an absurd game of chicken, right before a pivotal vote in the Senate, each side wary the other is about to betray them. It is grand political theater, except health insurance for millions of Americans are at stake.

Senate Republicans don’t want the House to pass their health care bill

One thing has become clear: Senate Republicans don’t actually have a plan to repeal and replace Obamacare. They don’t even, right now, have a bill. Now they are trying to come up with some bill — dubbed the “skinny repeal” bill — that can get 50 votes.

As outlined, it would eliminate the penalty for Obamacare’s individual mandate, possibly along with its employer mandate and some of its taxes on the health care industry. One lobbyist said the legislation could be narrowed to the “lowest common denominator product.”

If it were to become law, repealing the individual mandate could sending premiums skyrocketing in Obamacare’s insurance markets. Health insurers have long said that a compulsion for people to buy insurance is necessary in order for the law to work, after it required that insurers cover everyone and charge everyone the same premiums no matter their health.

Without such a mandate, healthy people could forgo coverage while sick people would continue to buy insurance, driving up costs for insurers, who in turn increase premiums, sending the market into a death spiral. The Congressional Budget Office estimated repealing the mandate by itself would lead to 15 million fewer Americans having health insurance 10 years from now.

Republican senators say they have been assured by their leadership that the skinny plan would only be a way to enter negotiations with the House. It is not intended to be an actual bill that will be sent to President Trump’s desk.

“The skinny bill doesn’t work for any state,” Sen. Lindsey Graham (R-SC) told reporters Thursday evening, as he threatened to oppose the skinny bill without guarantees from House leadership that they would enter negotiations. “The skinny bill does not replace Obamacare. The skinny bill leaves most of the Obamacare infrastructure in place. It’s a disaster for premiums in South Carolina. It was never sold to be the final product.”

There is widespread distrust among Republicans right now

The fundamental problem right now seems to be that Republicans don’t trust each other. Senators don’t trust the House. Republicans in the House don’t trust their peers in the upper chamber or each other.

The Senate doesn’t want the House to pass skinny repeal and send it to Trump’s desk. Instead, they want the two sides to negotiate yet another proposal. But some House members want to just go ahead and vote on skinny repeal: Graham said that House Freedom Caucus Chair Mark Meadows had called him and warned that there was a push in the House to simply pass the Senate bill.

According to Graham, Meadows told him, “There’s a move in the House to take whatever we pass in the Senate and pass it, not go to conference.”

“We’ve asked [Senate Majority Leader Mitch McConnell] point blank and he says [House Speaker Paul Ryan] prefers to go to the conference, intends to go to the conference,” Graham said. “Uh, I want to know, like, are you gonna go to the conference?”

Graham, along with Sens. John McCain, Ron Johnson and Bill Cassidy, are threatening to tank the Senate bill unless they receive such assurances from Ryan.

Johnson told reporters that he had sought guarantees from unnamed House members that they would not pass the Senate bill, but he had as of mid-afternoon Wednesday not received those assurances.

“I’ve reached out,” is all Johnson would say.

But on the other side, House Republican aides are balking at the Senate’s demands. In their view, they have passed a comprehensive bill and the Senate has failed to do so.

What right does the Senate have to demand anything of them?

“The House passed a real bill. The Senate is incapable of passing a real bill. So they’re passing the skinny repeal and demanding that we not take it up?” one House aide said. “I don’t think they’re in a position to demand anything from the House right now.”

House Republicans are maybe threatening to pass the Senate bill

The actual intentions of House Republican leadership are not clear. But there is plenty of smoke feeding the Senate’s fears that the lower chamber is ready to pass their bill and call it a day.

House leadership has warned their members to stay flexible over the weekend, in case the Senate passes a health care bill. One aide noted that could be simply so the House could vote to go to conference. But it also leaves open the possibility that the House rushes to vote for the Senate bill and send it to President Trump’s desk.

Health care lobbyists are hearing rumors that Ryan has told members they are ready to vote on the Senate bill. Some Republicans have said openly that they prefer to simply pass the Senate’s skinny bill.

Rep. Carlos Curbelo says he would support skinny repeal, and that he would prefer no conference before the House passes it. — Haley Byrd (@byrdinator) July 27, 2017

There are also strong hints from other House Republicans that passing skinny bill is their plan.

GOP dep whip tells me it's a definite possibility 'skinny' could pass House intact. In hands of @freedomcaucus. Expect big conf mtg in a.m. — Mike DeBonis (@mikedebonis) July 27, 2017

It’s impossible to separate what’s true and what’s not — and House leaders have not yet said what they intend to do.

“We’ll wait to see what they pass,” House Majority Leader Kevin McCarthy told the Washington Post’s Mike DeBonis.

At the same time, there is widespread doubt among congressional aides and health care lobbyists that conference negotiations would yield a more viable product. This “skinny” repeal bill might simply be the only viable product for a Republican Congress, after years of promises to uproot Obamacare root and branch.

“The problem for our side is if we go to conference, the only thing that could possibly come out (considering the way the Senate negotiations have gone) is something that looks very much like the skinny repeal,” the House GOP aide said. “So why bother with conference?”