WASHINGTON — One of Senate Majority Leader Mitch McConnell’s guiding principles is: “There’s no education in the second kick of a mule.”

Now, deep into a government shutdown he cautioned President Donald Trump against, McConnell is not about to let himself be kicked again.

The Republican leader has been conspicuously deferential to Trump since the shutdown began. He’s waiting on the president and Democrats to make a deal to end it. The result is an unusually inactive profile for the GOP leader who’s often the behind-the-scenes architect of intricate legislative maneuvers to resolve bitter partisan stalemates.

Democrats complain publicly — and some Republicans grumble privately — that the Senate is not fulfilling its role as a co-equal branch of government, a legislative check on the executive. They worry about ordinary Americans facing hardship waiting for a resolution to the standoff over Trump’s demand for money to build the border wall with Mexico.

But the Kentucky Republican, who is up for re-election in 2020 in a state where Trump tends to be more popular than he is, sees no other choice than to stand back and let the president who took the country into the shutdown decide how he wants to get out of it.

McConnell has plenty of solutions at the ready, allies say.

McConnell said the “solution to the problem” is for the president, who he reminds is the only one who can sign a bill into law, to reach an agreement with Democratic leaders Nancy Pelosi and Chuck Schumer. “There’s no way around that,” he told reporters this week.

Democrats wonder whatever happened to the mastermind of earlier legislative logjams. After all, the 30-year veteran of the Senate devised the way out of a debt ceiling crisis when tea party Republicans challenged then-President Obama; he brokered the deal with then-Vice President Joe Biden to avert the so-called “fiscal cliff.”

“A few years ago, Leader McConnell remarked, ‘Remember me? I’m the guy that gets us out of shutdowns,'” said Senate Minority Leader Chuck Schumer, unearthing an interview McConnell did some years ago. “Well, Leader McConnell, now’s the time…. allow a vote on legislation and reopen the government.”

McConnell has plenty of solutions at the ready, allies say. But he sees no value in trying to execute a deal that Trump may not ultimately endorse. It’s not only a waste of time, in his view, it potentially exposes Republican senators up for re-election in 2020, including himself, as sideways to Trump’s wishes.

“Everyone is demanding that McConnell ‘do something.’ What?” asked GOP strategist Scott Jennings, a longtime McConnell ally. “What is McConnell — or anyone else — going to tell Trump? Hey man, give up on the wall? That’s crazy.”

Jennings said rather than being seen as weak leader, the opposite is true: McConnell is showing strength by protecting Republicans from taking votes on bills that put them or the president on the spot as they try to force Democrats’ hand.

“He’s not going to undercut the president of his own party,” he said.

“He’s not going to undercut the president of his own party.”

No sense being on the other side twice. Days before the shutdown, McConnell started executing the plan Republicans had largely agreed upon.

The strategy was simple: Give Trump a runway to take the case to the American people — including during his State of the Union address — before the next round of voting in February, according Republicans familiar with the plan.

All systems were go until the morning of final passage, but Trump opposed it.

McConnell was frustrated. “He wasn’t very happy about it to say the least,” said retiring GOP Sen. Pat Roberts of Kansas. “He’s a very crafty individual… very strategic… Mitch, if something doesn’t work, he finds a way to make it work.”

But this time, McConnell is not providing the way out. Yes, he’s appearing at White House negotiating sessions. His staff meets for bipartisan talks with others. McConnell talks most every day to by phone to Trump. Asked about the senator’s role during the shutdown, the president heaped on praise: “He’s really been fantastic.”

Yet the leader, who was required to sit still as a child battling polio, is nothing if not a patient person. And so he waits.

Not all Republicans embrace the strategy. Some are growing anxious that Senate is essentially idle while hundreds of thousands of federal employees go without pay, wreaking havoc on their households and putting the broader economy at risk.

“Right now, it’s the Senate that really isn’t doing anything, I think we should do something,” said Sen. Ron Johnson, R-Wis., who is trying to build support for his bill to pay federal employees, including TSA airport security screeners, who are forced to work without paychecks.

“I’m very sympathetic with the fact that we do need the president to sign something — so what’s the point of bringing something up that’s DOA — but we certainly can show some leadership here,” he said. “We could bring that up for votes.”

As #MitchShutdown billboards dot the Kentucky countryside, McConnell, who will likely want Trump by his side as he runs for re-election, has given no indication he’s feeling the heat.

He’s likely more interested in voters like Mike Bickers of Lexington, a 65-year-old retired sales rep for Coca-Cola.

“I don’t want Mitch McConnell to cave on this,” Bickers said. “I want him to stick to his guns.”

Trump won Kentucky in 2016 with nearly 63 percent of the vote, some 400,000 more votes than McConnell in his last Senate election. In 2018 Kentucky voters again embraced Trump in re-electing GOP Rep. Andy Barr, the congressman who was in a tight race until Trump visited, beginning a surge in Barr’s favor.

McConnell’s approval ratings, nationally and in Kentucky, have never been high. But he has consistently been re-elected by running disciplined, well-funded campaigns.

One of the #MitchShutdown billboards is in Owensboro in western Kentucky, once a Democratic stronghold. Now its Republican mayor, Tom Watson, says he and many of the city’s voters are happy to see McConnell and Trump “totally agree on something” over the border wall.

“Senator McConnell,” said Watson, “I believe, is doing exactly what the Senate is supposed to do.”