By referring to Donald Trump as “Individual 1” in a criminal filing, and confirming that the President was involved in efforts to pursue a big Moscow real-estate deal deep into the 2016 campaign, the special counsel, Robert Mueller, appears to have set the Trump-Russia endgame in motion. In thinking about how it will play out, there are at least four things to bear in mind, all of which the past few days have highlighted: Mueller knows more than anybody else; he remains unlikely to bring criminal charges against Trump himself; the Republican leadership on Capitol Hill consists of invertebrates; and Trump is utterly shameless.

Even though BuzzFeed, in a remarkable report published in May, revealed many of the details of the Moscow caper that involved Trump’s personal lawyer, Michael Cohen, and Felix Sater, another longtime Trump associate, Cohen’s guilty plea on charges of lying to Congress surprised almost everybody. Outside of Mueller’s office, nobody can be sure what comes next. There have been reports that his investigation is now focussing on what Trump knew about the infamous June, 2016, meeting at Trump Tower with a group of Russians, as well as possible contacts between other Trump associates and WikiLeaks. Many observers believe that the special counsel is building toward an indictment of Roger Stone, a longtime Trump adviser.

In dragging Cohen into court on a perjury rap—earlier this year, Cohen made a separate plea agreement on charges relating to his own finances and his handling of the payoff to Stormy Daniels—the special counsel could be preparing to bring similar charges against others. But, if the targets of a follow-up indictment included a member of the Trump family, it would almost certainly be Donald Trump, Jr., rather than the President himself.

Last year, Trump, Jr., told Congress that he knew “very little” about the Moscow deal and wasn’t aware that Cohen had contacted the Kremlin for help. But, in the court filing that detailed the Cohen plea deal, Mueller baldly states that Cohen “briefed family members of Individual 1”—Trump, Sr.—“within the Company about the project.” The filing didn’t provide any more details, but the Wall Street Journal reported on Thursday that Mueller’s investigators “obtained emails about the project from late 2015 and January 2016, according to people familiar with the matter, in which Mr. Cohen communicated with or copied Mr. Trump’s son, Donald Trump Jr., and his daughter, Ivanka Trump, both of whom were executives at Trump Organization.”

The court filing, which Mueller signed, also says Cohen briefed Trump, Sr., about the Moscow deal more extensively than he had previously stated. Conceivably, the President could have committed perjury in the written responses that his lawyers submitted to Mueller last week—we know that Mueller asked about the Moscow project—although Rudy Giuliani insisted that his client’s answers were consistent with Cohen’s claims.

Even if there were a glaring inconsistency, however, Mueller would face formidable barriers to bringing a criminal charge against Trump. The Deputy Attorney General, Rod Rosenstein, explained earlier this year, “The Department of Justice . . . has opined that a sitting president cannot be indicted.” Evidently, Rosenstein regards that as settled policy. And, although Mueller has a good deal of independence in how he carries out his investigation, the regulations governing special counsels state that they “shall comply with the rules, regulations, procedures, practices and policies of the Department of Justice.”

Given these rules, it seems virtually certain that Trump’s fate will ultimately be determined in the political arena rather than the courts. Mueller, in his charging documents and sentencing memoranda, as well as in a final report to his superiors—whenever he presents it—can continue to lay out the crimes and malfeasances his investigators have uncovered, including any involving collusion, obstruction of justice, or lying under oath. But the responsibility of bringing Trump to book will most likely fall on Congress, and, ultimately, perhaps, the electorate.

Members of the new Democratic majority in the House of Representatives are already planning to have Cohen testify in the new year. “Obviously, you have to be a little bit ginger with anybody who’s been lying for a long time, but . . . he is clearly going to be a truth-telling refugee in Trump world,” Jamie Raskin, a member of the House Judiciary Committee, told Politico.

The Democrats will also use their newly acquired power to issue subpoenas. But will they also take the ultimate step of impeaching Trump? “Even if the Democrats don’t want to do it . . . they almost are going to have to look at it very, very seriously now,” the Georgetown law professor Neal Katyal, who was an acting solicitor general in the Obama Administration, said, on Chris Hayes’s MSNBC show. “Because this isn’t just criminal. This is the President campaigning in 2016 and hiding all of his negotiations with Russia.”

If the House did start impeachment proceedings, there would be a trial in the Senate. A conviction would require a two-thirds majority. Since the G.O.P. will have fifty-three seats in the upper chamber come January, such an outcome seems almost unthinkable. In another scenario, there wouldn’t necessarily have to be a trial. If some influential Republican senators informed Trump in advance that they were intending to abandon him, his position would be untenable. This is what happened to Richard Nixon, but there is still no sign of history repeating itself.

After Cohen’s plea, there was a deafening silence from senior Republicans. Rather than congratulating Mueller on informing the public about the Trump Organization’s entreaties to the Kremlin during the election campaign, McConnell and his colleagues were busy grumbling about their colleague Jeff Flake’s refusal to approve any judicial appointments until they agreed to a vote on a bill designed to protect Mueller from the whims of the President.

As long as Trump thinks that he has the Republicans in his corner, his defiance will know no bounds. Tweeting from Buenos Aires early Friday morning, he said that his decision to pursue business deals while running for President was “very legal & very cool.” He went on: “Lightly looked at doing a building somewhere in Russia. Put up zero money, zero guarantees and didn’t do the project. Witch Hunt!”

It’s tempting to dismiss such comments as mere bluster, but that might be a mistake. Trump’s shamelessness is combined with a propagandist’s conviction that if you say something often enough, loudly enough, it becomes true—or true enough to confuse people. His goal now is to plant the notion that anything short of outright criminality on his part is O.K., and to erase some of his past statements, such as the early 2017 tweet in which he said, “I HAVE NOTHING TO DO WITH RUSSIA - NO DEALS, NO LOANS, NOTHING!”

Mueller demolished that fiction. But the endgame has only just started.