WASHINGTON — Officially, Republicans blame Democrats for what on Saturday will be the longest government shutdown in the nation’s history. Privately, many concede, the stalemate over President Trump’s demand for a border wall has been made exponentially worse by White House ineptitude on Capitol Hill, where two years of contradictory statements and actions have built up a profound lack of trust.
Republican lawmakers and aides worry that Mr. Trump has misunderstood Democrats’ incentives to stand firm and that he has deputized the wrong aides to press his case. And they question who — if anyone other than the president — has the authority to resolve the impasse. They describe a dysfunctional dynamic where even senior leaders in Mr. Trump’s own party never know quite what to expect from the president.
“It’s always difficult when the person you’re negotiating with changes their mind — including my wife,” said Senator John Cornyn, Republican of Texas, when asked about the consequences of Mr. Trump’s penchant for doing so.
Mr. Cornyn noted that in the days before the shutdown began on Dec. 22, he and every other senator had voted for a stopgap government spending measure that omitted wall funding, believing that the president supported it, only to learn later that Mr. Trump had no intention of doing so. The president’s about-face — and House Republicans’ decision to add $5.7 billion in wall funding to the Senate bill — precipitated the shutdown, which reaches Day 22 on Saturday.
“My understanding was that the president was going to sign that, but apparently he changed his mind,” Mr. Cornyn said.
Such miscues and abrupt changes of course have become a staple of Mr. Trump’s dealings with Congress. The president has now repeatedly undercut Vice President Mike Pence, to whom he has delegated the task of negotiating an end to a seemingly intractable stalemate.
“It’s very difficult to be successful if there’s not predictability, reliability and trust,” said Phil Schiliro, who served as President Barack Obama’s legislative affairs chief in his first term. “For there to be a successful negotiation and for people to move off the position they came in with, members want to know that there’s going to be closure and agreement and cover at the end of the day.”
Mr. Pence denied on Thursday that he had ever told lawmakers that Mr. Trump would sign the bill, pressed personally by the majority leader, Senator Mitch McConnell of Kentucky, to keep the government open without funding for the wall.
“I said the president hasn’t made up his mind,” Mr. Pence said.
But that is not how Republicans remembered it.
“He got off to a bad start; he kind of pulled the rug out from under McConnell’s feet there with that one,” said Representative Francis Rooney, Republican of Florida.
It happened again on Thursday. A group of Republican senators were trying to forge a deal to pair wall funding with legal status for undocumented immigrants brought to the United States as children, often known as Dreamers. Then Mr. Pence told them that their effort would not earn Mr. Trump’s support, effectively torpedoing the talks. Members of the group said they recognized that their proposal would rise and fall according to the whims of the president.
“The president is the chief executive who is going to be a part of solving this problem,” said Senator Thom Tillis, Republican of North Carolina, “so I must trust him.”
But hours later, the president contradicted Mr. Pence, saying in McAllen, Tex., that he would be open to a “broader” immigration deal that would “simultaneously” deal with the Dreamers and a wall — if senators would bring him one they could agree on.
Again, Republicans were left baffled by a president who has pitched himself as an expert in the art of the deal.
“I wouldn’t want to comment on his unique style of negotiation and communications,” Mr. Rooney said. “Sometimes it’s worked very effectively for him, and sometimes it has confused a lot of people.”
The concern goes beyond Mr. Trump and Mr. Pence. Jared Kushner, his son-in-law and senior adviser, has also been asked to help resolve the wall impasse, but Mr. Kushner has no experience in crisis negotiations on Capitol Hill, and his attempts at intervention have borne little fruit.
The day before Mr. Trump’s prime-time Oval Office address to the nation, Mr. Kushner called Senator Joe Manchin III of West Virginia, a centrist known for his enthusiasm for bipartisan deals, and said the president was firmly committed to his position on the wall and did not plan to budge, according to two people familiar with the conversation, who spoke on the condition of anonymity because the call was private.
Mr. Kushner has little relationship with Mr. Manchin, but he left the senator with the impression that the White House believed public opinion would be on the president’s side after the speech, and that Democrats would simply have to relent. That did not go over well.
Inside the White House, officials privately acknowledge that the president dove into this fight with no clear end game. In several recent discussions with allies, Mick Mulvaney, the president’s acting chief of staff, has signaled he wants to reach a deal soon. During staff meetings over the past week, Mr. Mulvaney has said there was only a limited window for the White House to win the public-relations war around the shutdown.
But Mr. Mulvaney, who previously headed the Office of Management and Budget, has been in this new role for less than two weeks. Government shutdowns are difficult under the best of circumstances, and Mr. Trump is going through one in the midst of a protracted staff shake-up inside the West Wing and in his cabinet.
His legislative affairs chief, Shahira Knight, a former senior congressional aide who played a central role in pushing through Mr. Trump’s tax cut, has also never had to manage a protracted battle for Mr. Trump. She is well liked and respected by members of both parties, but regarded with suspicion by some of the president’s staunchest allies on Capitol Hill, including members of the conservative Freedom Caucus, who urged him to dig in for a wall fight even as she was counseling avoiding a shutdown, according to people familiar with the talks.
But his acting budget director, Russell T. Vought, earned the enmity of more moderate Republicans — and virtually every seasoned House Democrat — as a conservative warrior and favorite of the Freedom Caucus. Mr. Vought’s 15 years in Washington included a long stint with the conservative House Republican Study Committee, the Freedom Caucus’s predecessor, then with the Heritage Foundation’s political arm, which often clashed with House Republican leadership.
On Thursday, Republican senators who had expected Mr. Vought to attend a weekly luncheon and brief them on the president’s current thinking were surprised when he did not show up, according to one senior aide.
“He relies too much on the Freedom Caucus,” said Representative Peter T. King, Republican of New York, who broke this month with Mr. Trump and most members of his party to support Democrat-offered bills to reopen the government. “He thinks that they are speaking for all Republicans, and they’re not.”
Mr. King received a phone call from Mr. Trump last week asking him to vote against the measures to reopen the government, he said, adding that he refused. “The president has to make real concessions,” Mr. King said, “and so do the Democrats.”
But Mr. Trump’s assumptions about what Democrats will give in on, and what is motivating them, have also been almost comically wrong.
Early this month, at a negotiating session in the White House Situation Room, Mr. Trump and his team said Speaker Nancy Pelosi of California, at the time on the eve of her election to the top post, would be more willing to give in on the wall once the vote was behind her. But with the gavel in hand and an energized new class of liberal Democrats enthusiastically supporting her, Ms. Pelosi only dug in.
More recently, that line of thinking has shifted to one Mr. Trump described to senators on Wednesday in a closed-door lunch at the Capitol: that Democrats would be ready to cut a deal with him once federal employees started missing paychecks.
That milestone was reached on Friday, with no deal in sight.