With this week’s budget and its official embrace of tying Social Security benefits to the “chained” consumer price index, Barack Obama officially becomes the first Democratic president in history to propose any cuts to the program so venerated and beloved by liberals everywhere. Put that way, it sounds completely indefensible. The reality, of course—well, not “of course” to a lot of people, but “of course” to me—is that the Republicans will never accept tax increases, so it’s all fictional anyway. So assume with me no deal and ponder the politics of this, heading into 2014 and even into 2016. If things go the way I think they will, Obama and the Democrats will come out of this looking good, although almost entirely by accident.

As you should know by now, indexing Social Security benefits to the chained CPI will reduce benefits especially as recipients get into their 80s. Obama wants cushions built into the new indexing that will soften the blow for these people and says it’s a precondition for his own support for the change. The other precondition is Republicans agreeing to revenues. If those don’t happen, he says, he takes chained CPI off the table and becomes the first Democratic president ever to offer a cut to Social Security and then withdraw it.

And this is what is almost certainly going to happen. Republicans, from John Boehner and Mitch McConnell to Paul Ryan to Ted Cruz to every Dixie back-bencher, have said it a thousand times if they’ve said it once: Obama got his revenue in the fiscal-cliff deal. No more.

Do you see any reason not to take them at their word? I see none. The only argument against this is that indeed, back in January, as the fiscal-cliff clock was ticking down to midnight, Republicans did agree to some revenue increases. But in the Senate, nearly every Republican voted for a bill that watered down Obama’s revenue requests considerably (he’d wanted a higher rate to kick in on dollars earned above $250,000, but the Senate changed it to $450,000). And in the House, only 85 Republicans backed the agreement. John Boehner had to break the Hastert rule to get the deal through. His top deputies voted against it. There was a big pile of commentary at the time about how it weakened him within his caucus.

Those votes came to pass for one reason and one reason only: tax rates on all Americans were about to go up if Congress didn’t act. And so, Congress acted. Period. Now that is off the table, and off the table for good—the worst aspect of the fiscal-cliff deal is that it made the Bush rates permanent instead of Congress having to renew them every five years. So that’s what made the fiscal-cliff deal come together, and it’s why so many Republicans in the Senate and just enough in the House backed it.

But that particular sword of Damocles has floated off into the ether. There is no similar pressure point today that would make Republicans accept more revenues. So in my view, they won’t. This general and vague “public pressure” that some folks discuss with hope doesn’t exist for today’s GOP. If they can find ways to mock and minimize and ignore public opinion on background checks, they’ll do it on everything.

And let’s just imagine for the sake of argument that McConnell and Boehner did agree to a deal. Would such a compromise, including tax revenues substantial enough for Obama to agree to it, get enough GOP votes to pass? Remember, in the Senate Obama would lose a few votes on the left—Bernie Sanders for sure, maybe two or three others. And in the House, Obama would lose, oh, 30 or 40 (or more) liberal Democrats, meaning that passage—of a bill to raise taxes!—would depend on Republicans. No chance.

It’s an interesting question whether Obama knows this. Theory A is that of course he knows this perfectly well, so he knows the chained CPI change will never happen. He just wants to look to swing voters like he’s Mr. Reasonable so the Republicans will look unreasonable and he can hit the 2014 campaign trail saying: “Hey, look, I tried. But these people are incorrigible. It really ought to be clear to you by now, Mr. and Mrs. America, that they are the obstacle, and that if you want anything done in this town, you have to give me a Democratic majority in the House so we can do some legislating.”

Theory B is that Obama still somehow thinks, after all this time, that he can get the GOP to see reason and come to terms. Under this theory, he’s not crazy about chained CPI and is putting it on the table perhaps against his better judgment, but he’s just trying to show that he stands ready to deal.

Theory C is that Obama just genuinely thinks chained CPI is good policy. This is the view of people on the liberal-left end of the spectrum who haven’t trusted him ever since he failed to prosecute the double Dicks (Cheney and Fuld).

I think B is what Obama thinks. He seems to believe they’ll come around. As part of this, I think that while he has reservations about chained CPI, he is willing to trade it for some of the priorities he laid out in his State of the Union address. Universal pre-K, for instance. In policy terms, there exists some inevitable trade-off in whether government will invest in the old or the young, and it wouldn’t shock me to know that on balance, Obama favors the young. That’s a debate liberals need to have and should be able to have without exchanging gunfire.

But it doesn’t matter what Obama thinks. What matters is what is. And what is, is A. There will be no deal. The mechanism that forced GOP acquiescence on the fiscal cliff, the prospect of higher taxes for all, is gone, never to return. Nothing else will bring Republicans to any table. I wish centrists in this town would just get over this delusion. There is no negotiating with them. There is only one thing to do with them. Beat them.