(JOSHUA ROBERTS/BLOOMBERG)

On Tuesday, the Gang of Six proposed a deal that would raise tax revenues by $2 trillion — which showed there was support among Senate Republicans for a deal that raised taxes by about $2 trillion. On Thursday, congressional Democrats rebelled over reports that the deal Boehner and Obama were negotiating had only $800 billion in new revenue, and it wasn’t even clear how those would be achieved. That night, Obama called Boehner looking for about $400 billion more in revenue to have something he could sell to Democrats. That would have brought the deal from $800 billion in revenue to $1.2 trillion in revenue. He didn’t get a call back until the next day at 5:30 p.m. — by which point the call was unnecessary. Boehner had already told the media that he was leaving the talks.

Republicans are emphasizing that the White House went from asking for $800 billion in revenue to $1.2 trillion. The word you’re hearing from them is “reneged,” but the White House emphasizes that negotiations were ongoing, and both sides were asking for more as they tried to figure out what they could both agree on and pass through Congress. Boehner, for instance, wanted further cuts to Medicaid, a trigger that would repeal the individual mandate and the Independent Payment Advisory Board if the entitlement cuts didn’t come through, and a tighter cap on discretionary spending. “They make it seem like the president made some ultimatum on $1.2 trillion in revenue,” says a senior administration official. “He didn’t. He said, ‘If you can’t do this, let’s figure out what we can do.’ ”

The “what we can do” would probably have been to ratchet back the entitlement cuts. Or maybe another solution would have been found. It’s hard to say because Boehner didn’t come back with a counteroffer. He simply left the negotiations.

But let’s zoom out on where the negotiations left off. Spending cuts would have totaled about $3 trillion, with a bit less than a trillion dollars of that coming from entitlements and other forms of mandatory spending. Revenue increases — none of which would have come from raising marginal tax rates — would have been between $800 billion and $1.2 trillion. The package would have extended the unemployment insurance and payroll tax cut provisions passed in the 2010 tax deal. All in all, that’s about a trillion dollars less in revenues than the Simpson-Bowles/Gang of Six deals advocated, and about $2.6 trillion less in revenue than simply letting the Bush tax cuts expire in 2012.

There’s a question as to whether this was the very best deal Republicans could get or simply close to it. But it’s hard to believe that it was so bad that it ended the talks. What seems likelier is that Boehner spent some time between Thursday and Friday talking to his members and found that his party simply didn’t support a deal with the White House. For one thing, a deal would include some amount of revenue, and that was a hard sell under any circumstances. For another, letting the president look like a dealmaker would potentially dim the GOP’s chances of retaking the White House in 2012. As my colleague George Will put it Thursday, a deal “would enable President Obama to run away from his record and run as a debt-reducing centrist.”

And so Boehner walked. Fundamentally, this looks like the same calculation that ended the last round of talks over a 4 trillion deal. What’s different this time is Boehner’s plan B: The Speaker of the House appears to believe that a deal struck between congressional leadership would perhaps be easier to sell to his members. Since it’s hard to see Nancy Pelosi and Harry Reid making deeper concessions than Obama did, it’s hard to see why that would be true, save that the deal might not look like such a victory for the White House.

Perhaps taking the benefit for Obama off the table will be enough. I’m doubtful. It’s more likely that what we’re really doing now is wasting time until the markets plummet and Boehner’s members decide that a deal is better than no deal. And there’s a very good chance that the first major show of market concern could come tomorrow night, when the Asian markets open. Boehner is hoping to present a plan by then, but a plan is very different from a deal. A plan is something politicians can come up with. A deal, we’re increasingly finding, is something that we need the markets to force.

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