When President Donald Trump visited the CIA Saturday, he had hoped that CIA Director Mike Pompeo would accompany him. But when Trump arrived at the Langley, Virginia, headquarters of the Agency, he was instead accompanied by Congressman Mike Pompeo.

Representative Pompeo will almost certainly be confirmed as CIA Director on Monday. And the CIA will no doubt survive two days without its new leader. But the nastiness of the partisan sniping between top Republicans and Democrats that led to the delay may well have a lasting impact on the Senate - in this Congress and beyond.

According to six sources familiar with the negotiations over Pompeo's confirmation, Senate Minority Leader Chuck Schumer told Republican leaders that he would allow Pompeo to be confirmed by voice vote on Inauguration Day, along with two other Trump nominees who have national security responsibilities. But Schumer broke his promise, these sources say, and offered an insulting excuse for having done so.

"Trust is important, even between adversaries," says Senator John Cornyn, one of the Republicans involved in the discussions. "And that trust has been damaged."

The story begins in early January, before the Senate held a single confirmation hearing for any of Trump's nominees. Senate Republicans scheduled six confirmation hearings for January 11, a Wednesday. The schedule complicated the plans of Senate Democrats, who had hoped to mount challenges to several Trump nominees – or at least create news by attacking them. Too many hearings would spread thin the coverage of made-for-media battles. So Democrats formally objected. "Not acceptable. I've told that to Mitch McConnell," Schumer said in an interview with Politico. "I don't think my members would find what they did appropriate or acceptable."

According to sources familiar with the discussions, Schumer asked his Republican colleagues to delay Pompeo's hearing for one day. "Democrats asked that the hearing be moved so that six hearings did not occur on one day," says a senior Democratic senate aide. "That many cabinet hearings in a single day had only happened once in American history, and it was an unfair schedule to senators on both sides. Republicans accommodated that request."

Among the reasons Schumer cited: Senator Dianne Feinstein, who had until this Congress been ranking member on the Senate Intelligence Committee and is currently ranking member on Senate Judiciary, complained that the schedule would prevent her from attending hearings for both Pompeo and Attorney General nominee Jeff Sessions.

McConnell consulted Senate Intelligence Committee Chairman Richard Burr, Intel committee member Tom Cotton, and the incoming Trump administration. Republicans agreed to delay Pompeo, whose team was happy to have an extra day to prepare. But the Republicans had a condition. If we agree to push back Pompeo's hearing for a day, they told Schumer, you must agree to include him in the group of national security officials who will be confirmed by a voice vote on Inauguration Day, January 20. According to these sources, Schumer agreed, with alacrity, having secured the delay he'd sought.

But on January 19, one day before Trump's inauguration, Ron Wyden said he'd seek to delay Pompeo's confirmation when the Senate convened late Friday afternoon. That evening Cotton, who is close to Pompeo from their time together in the House of Representatives, began calling his colleagues on the Senate Intelligence Committee, including Wyden, seeking to avoid the delay. Some of the calls were cordial. Others were testy.

The Senate reconvened after the inaugural ceremonies on Friday, with Pompeo's nomination set to come up at 4:50pm. Cotton angrily confronted Schumer about his broken promise. According to witnesses, Schumer told Cotton to lower his voice and asked him move off of the Senate floor to an adjacent hallway for a private discussion. "We need to take this out into the hallway," Schumer said. Cotton walked with Schumer but loudly rejected his first request. "Don't tell me to lower my voice!" he shouted, with an additional salty admonition tacked on for emphasis. Burr and Cornyn were present, as was Senator Mark Warner, ranking member of the Senate Intelligence Committee, and several aides.

Schumer told Cotton that the Senate had never previously confirmed a CIA director on Inauguration Day and if Cotton had been around eight years earlier, he'd know that Republicans didn't extend that courtesy for incoming president Barack Obama. "Eight years ago, I was getting my ass shot at in Afghanistan," Cotton snapped. "So don't talk to me about where I was 8 years ago."

Cotton asked Schumer why he'd gone back on his word. Schumer claimed that he'd only been speaking for himself when he promised to let Pompeo through. "I said that I would not block him," Schumer said, emphasizing the personal pronoun, according to sources who witnessed the exchange. "I never said that I could speak for 47 other Democrats."

The Republicans were stunned.

"I'm not telling Ron Wyden to do this," Schumer declared. "Why don't you go talk to Wyden?"

"That ain't my job, Chuck," said Burr.

"I know what you promised me," said Burr. "You made the deal!"

Cornyn recalls: "That's when [Schumer] started dissembling and said: 'I don't control my whole caucus.' Either he'd lost control or he was trying to make excuses for an outcome he wanted."

Burr, not known for his aggressiveness, pointedly told Schumer that Republicans had learned something important about taking Schumer at his word. "I won't make that mistake again," he said.

A Senate Democratic leadership aide disputed this version of events. "There was never a deal to confirm Rep. Pompeo on Friday. The senate has never confirmed a CIA director on inauguration day in American history, and we asked the Vice President to keep Director Brennan on the job, as Director Hayden stayed on before Director Panetta was confirmed. The incoming administration declined."

"I wish Senator Wyden had accepted our offer to conduct the debate he sought on Friday afternoon and I wish Senator Schumer had delivered on his agreement for a Friday vote," said Cotton. "But I look forward to a large bipartisan vote to confirm Mike on Monday."

Trump appeared at the CIA Saturday afternoon and gave a long, extemporaneous statement on threats to the US; intelligence community members who voted for him; Reince Priebus, a political "superstar;" the nomination of Sonny Perdue to be Secretary of Agriculture; the election and his "tremendous, tremendous success;" his strong belief in academics; the "dishonest media;" and the crowd size at the inauguration, which Trump estimated at 1.5 million.

Trump did also mention Mike Pompeo and his nomination to run the CIA. "He was approved basically but they're doing little political games with me," Trump said.

And on that, at least, he was right.