Republicans have dealt with some embarrassing moments on the House floor over the past year, but none so revealing or damning as today’s snafu, when they yanked a bill to fund the Departments of Transportation and Housing and Urban Development. Even the recent farm bill fiasco wasn’t as significant an indictment of the GOP’s governing potential.

It might look like a minor hiccup, or a symbolic error. But it spells doom for the party’s near-term budget strategy and underscores just how bogus the party’s broader agenda really is and has been for the last four years.In normal times, the House and Senate would each pass a budget, the differences between those budgets would be resolved, and appropriators in both chambers would have binding limits both on how much money to spend, and on which large executive agencies to spend it.

But these aren’t normal times. Republicans have refused to negotiate away their budget differences with Democrats, and have instead instructed their appropriators to use the House GOP budget as a blueprint for funding the government beyond September.

Like all recent GOP budgets, this year’s proposes lots of spending on defense and security, at the expense of all other programs. Specifically, it sets the total pool of discretionary dollars at sequestration levels, then funnels money from thinly stretched domestic departments (like Transportation and HUD) to the Pentagon and a few other agencies. But that’s all the budget says. It doesn’t say how to allocate the dollars, nor does it grapple in any way with the possibility that cutting domestic spending so profoundly might be unworkable. It’s an abstraction.

Indeed, Paul Ryan’s entire reputation rests upon these kinds of abstractions. His budgets imagine huge cuts to Medicaid and food stamps and Medicare and so on, but they have no binding force. His allure to the conservative movement as a vice presidential nominee was that he’d be uniquely suited to turn these abstractions into reality.

But many close Congress watchers — and indeed many Congressional Democrats — have long suspected that their votes for Ryan’s budgets were a form of cheap talk. That Republicans would chicken out if it ever came time to fill in the blanks. Particularly the calls for deep but unspecified domestic discretionary spending cuts.

Today’s Transportation/HUD failure confirms that suspicion. Republicans don’t control government. But ahead of the deadline for funding it, their plan was to proceed as if the Ryan budget was binding, and pass spending bills to actualize it — to stake out a bargaining position with the Senate at the right-most end of the possible.

But they can’t do it. It turns out that when you draft bills enumerating all the specific cuts required to comply with the budget’s parameters, they don’t come anywhere close to having enough political support to pass. Even in the GOP House. Slash community development block grants by 50 percent, and you don’t just lose the Democrats, you lose a lot of Republicans who care about their districts. Combine that with nihilist defectors who won’t vote for any appropriations unless they force the President to sign an Obamacare repeal bill at a bonfire ceremony on the House floor, and suddenly you’re nowhere near 218.

Yes, the House can pass things like the defense appropriations bill. But only because they’ve plundered other programs to provide the Pentagon with consensus-level funding. They can’t fund most of the rest of the government without violating the Ryan budget.

“With this action, the House has declined to proceed on the implementation of the very budget it adopted three months ago,” said an angry appropriations chair Hal Rogers (R-KY). “Thus I believe that the House has made its choice: sequestration — and its unrealistic and ill-conceived discretionary cuts — must be brought to an end.”

All of this is a harbinger for the coming fight over funding the government. If House Republicans can’t establish a position of their own, then the Senate will drive the whole process (its Transportation/HUD bill will probably pass on a bipartisan basis this week) and appropriations will be extended past September one way or another on the strength of Democratic votes.

It also suggests that the GOP’s preference for permanent sequestration-level spending, particularly relative to increasing taxes, is not politically viable. If they want to lift the defense cuts, they’re going to have to either return to budget negotiations with Democrats, or agree to rescind sequestration altogether.

But it raises much bigger, existential questions for the Republicans as a national party. If they can’t execute key elements of their governing agenda, even just to establish their negotiating positions opposite the Democrats, what can they do, and what argument can they possibly make for controlling more (or all) of Washington?