Most unnerving for many here was the realization that Mr. Papadopoulos had been secretly arrested three months ago and cooperating with prosecutors ever since. Former colleagues sought to remember contacts they had with him, either last year when he was reaching out to the Russians or in recent weeks when he was working for the authorities.
“Is there a darker cloud over the Trump presidency? The answer is yes,” said Ed Rogers, a prominent lobbyist and White House veteran of two Republican presidencies. “Is it a thundershower or a hurricane setting in? Nobody knows.”
Mr. Trump argued for drizzle, dismissing Mr. Manafort’s indictment on charges of money laundering and foreign lobbying as unrelated to the campaign and belittling Mr. Papadopoulos as a nobody. “Few people knew the young, low level volunteer named George, who has already proven to be a liar,” Mr. Trump wrote on Twitter on Tuesday in his first comment on the foreign policy adviser he once called an “excellent guy.”
Instead, as he has done repeatedly in recent days, Mr. Trump sought to turn attention to Democrats, pointing to the resignation of Tony Podesta, the powerhouse Democratic lobbyist who also faces scrutiny by Mr. Mueller and whose brother, John D. Podesta, was Mrs. Clinton’s campaign chairman.
“The biggest story yesterday, the one that has the Dems in a dither, is Podesta running from his firm,” Mr. Trump wrote. “What he know about Crooked Dems is earth shattering. He and his brother could Drain The Swamp, which would be yet another campaign promise fulfilled. Fake News weak!”
In a city where everything seems to break down along party lines, reaction to the indictments was no different. “If you’re a never Trumper, or if you’re with the media or a Democrat, this just confirms your wildest fears that Vladimir Putin is now running the White House,” said John Feehery, a Republican strategist. “But if you’re a Republican, you don’t see that this advances the narrative at all.”
Senator John Kennedy, a Republican from Louisiana, sounded ho-hum, saying the charges claimed tax fraud and lying to F.B.I. agents. “If those allegations are true, you’ve got to wonder how those individuals made it through the birth canal, because it was bone-deep stupid,” he said. “But I don’t know what they have to do with President Trump’s campaign.”
Credit Gabriella Demczuk for The New York Times
Other Republicans appeared eager to skirt the issue. Senator Mitch McConnell of Kentucky, the majority leader, shut down questions related to the case at a news conference on Tuesday. “The special counsel has his job to do, and we’re going to concentrate on what we’re doing here in the Senate,” Mr. McConnell said.
Senator Charles E. Grassley, the Judiciary Committee chairman, slipped past a stand of flags to leave a news conference Monday through the back door rather than take questions about the investigation, although he later spoke with reporters about the case.
Much of the talk on Capitol Hill centered on whether Congress needed to prevent Mr. Trump from firing Mr. Mueller. Senator Lindsey Graham was one of two Republicans who hastily introduced bills aimed at adding a layer of job security for Mr. Mueller in August. In the months since, the legislation has stalled, despite Democratic prodding.
“I don’t feel a sense of urgency, no, I don’t,” Mr. Graham said on Tuesday. “This is something manufactured by the people in your business. I haven’t seen anybody in the White House say anything to suggest there is a reason Mr. Mueller needs to be dismissed.”
Mr. Grassley was indignant at the question. “It’s ridiculous for anybody to be asking me about firing,” he said. “That’s not an issue in the White House.”
The administration acknowledged that the investigation was disrupting its agenda. “It is very distracting to the president, as it would be to any citizen, to be investigated for something, while at the same time trying to carry the weight of what being president of the United States means on his shoulder,” John F. Kelly, the White House chief of staff, told Laura Ingraham on Fox News on Monday night.
He suggested the investigation might wind down. “It should wrap up soon,” Mr. Kelly said. “I mean, it would seem that they’re toward the end of the witness pile and I don’t know how much longer it could possibly go on, but we’re in great hopes that it wraps up.”
That seemed to rank optimism over experience, given past investigations involving other presidents. Veteran lawyers said Mr. Mueller’s inquiry could last for months if not years.
After venting on Twitter in the morning, the president tried to refocus attention on his tax-cutting package set to be released this week. Hosting business leaders at the White House, Mr. Trump said he wanted the House to pass the bill by Thanksgiving and the Senate by Christmas, a blindingly quick schedule for such major legislation even without the shadow of scandal.
“Every president, Republican or Democrat, always has distractions,” Jay Timmons, the president of the National Association of Manufacturers and one of Mr. Trump’s guests, said afterward. “That’s where leadership really counts. Leaders are able to focus on more than one thing and this president is focused — I think rightly so — on what it takes to grow this economy and create more jobs.”
But the investigation, coupled with the dysfunction and polarization in Washington, makes the chances of passing major tax legislation by the end of the year problematic. “No one on Capitol Hill expects that to occur anytime soon,” said Jim Manley, a longtime Senate Democratic aide. “And in the meantime, they’re once again in a position where all these things are going to pile up.”
The president and Congress have until Dec. 8 to agree on spending bills to keep the federal government from closing down and have a limited window beyond that to raise the national debt ceiling to avoid a default. Mr. Trump and lawmakers are also at odds over legislation to prevent the potential deportation of young immigrants brought to the country illegally as children.
“The partisan in me wants to get another tub of popcorn and another glass of wine and watch how it all plays out,” Mr. Manley said. “But the former staffer in me is anxious to see this darkness leave so we can get back to legislating. I see nothing but chaos from here on out.”