It has been an annual rite in Washington since the modern budgeting system began in 1974: The president sends his budget to Congress, and lawmakers hold hearings on it.

But not this year.

The chairmen of the House and Senate budget committees announced, for the first time since their panels were created more than 40 years ago, that they would not have hearings on the president’s budget or allow administration officials to testify. They decided this before President Obama released his budget, refusing to contemplate any budget from Obama — sight unseen.

This declaration, like the Senate Republicans’ vow that they will refuse to consider — or even meet with — any Supreme Court nominee Obama sends them, is the very definition of blind obstruction.

The Senate Banking Committee refused to take action on any Obama nominee for 14 months, finally approving on Thursday the head of the Treasury Department’s terrorism section after letting him languish for 11 months. Why the delay? The chairman, Richard Shelby of Alabama, admitted that it was because he faced a primary challenge: He couldn’t be seen as approving any Obama nominee.

The number of judicial and executive branch confirmations overall is at the lowest point in decades. Lawmakers are postponing action on a budget and have failed to produce funds to deal with the crises involving the Zika virus, opioid addiction and the tainted water in Flint, Mich.

And Republicans wonder how they wound up with Donald Trump?

The party is in an existential crisis, and this sort of mindless obstruction, practiced on Capitol Hill for much of the past seven years, is partly to blame. Republican lawmakers, fearing pressure and primary challenges from extreme conservatives, refused to engage in anything that might be perceived as cooperating with Obama — and so the legislature ground to a halt. The failure to produce, or to do much to address the nation’s economic and security woes, caused more disgust with Washington. This, in turn, allowed the rise of a populist demagogue.

“If our self-indulgent Republican party establishment had really wanted to prevent a takeover of the GOP,” Republican consultant Alex Castellanos told The Post’s Tom Hamburger and Matea Gold this month, “they should not have gorged on political power while they failed to do anything to prevent the decline of the country. Our leaders could have led. They could have done more than say ‘no’ to Democrats while offering no alternative.”

Now, approval of Congress is at 13 percent in the latest Gallup poll, near record lows. Republicans are more down on Congress than Democrats, even though the GOP controls both chambers.

Obama, in a news conference Thursday, attributed the Trump phenomenon to “a notion that everything I do is to be opposed; that cooperation or compromise somehow is a betrayal.” This, he said, made “an environment where somebody like a Donald Trump can thrive.”

And still Republicans in Congress continue to say no.

House Speaker Paul D. Ryan had said this would be a “Year of Ideas,” with legislation aimed at poverty and health care. But the House has conducted legislative business on only 154 of the 431 days since this Congress began. Much of that time has been devoted to the obscure (this month’s legislation to delay regulations for brick kilns) and the symbolic (nine Republicans opposed naming a post office after the late poet Maya Angelou, and two of them called her a “communist sympathizer”).

And the Senate? Republicans once complained about all the House-passed bills that didn’t make it through the Democratic Senate. But at this point in 2014, there were 205 House-passed bills awaiting action; now there are 298 House-passed bills awaiting action by the GOP-controlled Senate.

The day Obama asked Congress to take action on closing the Guantanamo Bay prison, Sen. Pat Roberts (R-Kan.) released a video of him throwing a printout of Obama’s plan in the trash. The Senate spent four weeks on an energy efficiency bill and still hasn’t finished. It spent two weeks on opioid legislation, then passed it without funding. Conservatives’ objections also stalled bills addressing criminal-justice reform and Flint’s water.

After years of complaints from Republicans about the Democratic majority’s failure to pass a budget, the GOP-controlled Senate Budget Committee — the same panel that refused to consider Obama’s budget — just postponed action on its own budget.

The reason behind all this inaction is almost always the same: surrendering to the far right. Shelby was only being more honest than most with his four-word explanation for why he brought his Banking Committee to a halt: “I’m in a primary.”

But in their zeal to placate tea party conservatives, Republican officials created a leadership vacuum that has been filled by something far worse.

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