For the last few years — or at least since Republicans took the House of Representatives — there’s been a pattern to budget negotiations. In an attempt to claim the center and move the ball forward on a “grand bargain,” President Obama will make concessions in an area of concern to liberals. During his negotiations with John Boehner in 2011, he offered to cut Medicare in exchange for a relatively small amount in new revenue. Likewise, in the negotiations over the fiscal cliff, he offered a Social Security cut — “Chained CPI,” a different measure of inflation — in exchange for, again, new revenue. That Chained CPI proposal will be in the budget Obama sends up to the HIll tomorrow.

But with their categorical opposition to new taxes, Republicans could never take either deal. And while conservatives continued to make a case for deeper spending cuts than the president proposed, the practical effect of their refusal was to protect retirement programs like Social Security and Medicare from Obama’s push to trim their costs and reduce their benefits.

As The Hill reports this morning, liberals are hoping for a repeat of this dynamic with Obama’s latest budget, which enshrines entitlement cuts as a goal for the administration:

“They won’t give, and that just creates the situation where nothing moves,” Rep. Raúl Grijalva (D-Ariz.) said of the GOP’s stand against new revenues. “And if nothing moves, then you can’t put Medicare or Social Security on the table. … It’s an interesting way to look at it, but there might be more than a kernel of truth in that.”

If GOP calls for serious deficit reduction has spurred the administration to propose cuts to entitlement programs, then Republican intransigence on new revenues — Obama’s only condition for cutting either Social Security or Medicare — is what keeps those cuts from ever becoming law. Indeed, this isn’t conjecture — as soon as it was announced Obama’s budget would contain entitlement cuts, Speaker Boehner released a statement reiterating his opposition to new revenues or tax increases:

“When the president visited the Capitol last month, House Republicans stated a desire to find common ground and urged him not to make savings we agree upon conditional on another round of tax increases. If reports are accurate, the president has not heeded that call. If the president believes these modest entitlement savings are needed to help shore up these programs, there’s no reason they should be held hostage for more tax hikes. That’s no way to lead and move the country forward.”

If this is any indication, odds are good that liberals will — again — be able to count on Republican anti-tax dogma to shield retirement programs from further cuts. Or, as Ezra Klein noted recently, John Boehner has become one of liberalism’s most reliable allies.

All of this highlights a larger patter. Republicans push hard for large spending cuts — hence the Ryan budget and its various permutations. In election years, however, the GOP becomes a fervent defender of retirement programs — in 2010 and 2012, Republican candidates blasted Democrats for “gutting Medicare” and cutting benefits.

By proposing cuts to Social Security and Medicare, Obama has given cover to the GOP if it wants to pursue this strategy a third time in the 2014 elections. And if Republicans manage to win seats as a result, Obama will have harmed his position far more than if he had just ignored calls to “lead” on entitlements.

Jamelle Bouie is a staff writer at The American Prospect, where he writes a blog.