From September 17th until Election Day, President Trump tweeted nothing at all about the “witch hunt” by the special counsel, Robert Mueller, that had previously been a staple of his Twitter storms. With the midterm campaign in full swing, Trump showed that he was capable of restraint on the subject of Mueller, if only because he perceived a political benefit to his silence, reminding us that, no matter how scattershot, emotional, and impulsive his tweets seem, there are times when the President does practice a form of self-discipline. Trump clearly did not think it was a good idea to remind voters before the election that he is under investigation for serious potential crimes, including alleged conspiracy with the Russian election hacking of 2016 and obstruction of justice.

So much for restraint. Within hours of his party losing the House of Representatives anyway, the President immediately returned the Mueller investigation to center stage, firing his Attorney General, Jeff Sessions, replacing him with a public critic of the Mueller investigation, and resuming his attacks on Mueller’s “disgusting Witch Hunt.” On Thursday morning, beset by negative media coverage about the possible unconstitutionality of his choice of the acting Attorney General, Matthew Whitaker, and having reportedly spent hours closeted with his lawyers going over answers to Mueller’s queries, Trump was back to full-on Twitter attack mode: “A TOTAL WITCH HUNT LIKE NO OTHER IN AMERICAN HISTORY.”

The President is scared, and he is right to worry. I spent Wednesday on Capitol Hill, watching the real-time power shift as the House convened for its first post-election votes and members began the process of organizing for a new Democratic regime that will be defined by its aggressive efforts to investigate Trump and his Administration. Trump’s big sulk since the election suggests that the new reality of his political situation is starting to sink in, but I doubt he has fully reckoned with the consequences of pursuing a course of direct confrontation with another branch of government run by his diehard opponents. Richard Nixon, during Watergate, pushed the special prosecutor to the Supreme Court and lost when he refused to turn over the secret White House tapes. That course sank him in Congress. Reading Trump’s tweets this morning, I couldn’t help but wonder whether this President is also setting himself on a path toward a perilous legal confrontation over constitutional prerogatives.

In an interview, Representative Adam Schiff, of California, described to me his evolving plan to act as Mueller’s congressional backstop, insuring that, even if Trump and Whitaker attempt to shut down the investigation, Mueller’s investigatory work and conclusions will not be covered up. Schiff, who is expected to secure the chairmanship when Democrats approve their new leadership, also made it clear that he will revive and expand the committee’s investigation of the Russia allegations that Republicans on the panel abruptly shut down earlier this year, telling me he would like to recall Steve Bannon, Trump’s former strategist, and Michael Cohen, the President’s estranged former lawyer and fixer, among others, to get answers that the G.O.P. majority wouldn’t or couldn’t extract.

Most urgent is the crisis Trump has provoked in firing Sessions and installing Whitaker. Before our interview, Schiff had published a Washington Post op-ed, on Monday, promising, “Matthew Whitaker, we’re watching you.” In our conversation Schiff expanded on that, saying he was determined to “discover and expose any kind of wrongdoing” regarding the Mueller investigation. “If he takes any action adverse to the investigation or communicates any facts of the investigation to the President or his legal counsel, we’re going to find out about it,” Schiff told me. “There was a strong norm established after Watergate that the White House doesn’t intervene in specific cases. Now this is a specific case that involves the President, and this would go well beyond intervening. This would be affirmatively appointing someone to hinder the investigation.”

Schiff, a former federal prosecutor in California, said that he believes the Justice Department under Trump has set a precedent by turning over internal documents to the House Republicans in the Mueller probe and the investigation of Hillary Clinton’s e-mails that it would have to follow if Schiff demanded information regarding Whitaker’s actions involving Mueller. “They established a precedent, and I told them, ‘You are going to have to live with this,’ ” Schiff said. “ ‘Someone is going to be bereaved at the end of the Mueller investigation, and how are you going to say that the Democratic majority is not entitled to the same access to the materials that you have provided in the Clinton investigation or even in the Mueller investigation?’ ”

As for resurrecting the Intelligence Committee’s own Russia investigation, Schiff said the first step involves pushing to immediately release the transcripts from the panel’s interviews with key figures in the Mueller investigation; the committee has already voted to do so but never followed through. Schiff suggested that some of those who testified—he named the rogue Republican consultant and sometime Trump friend Roger Stone as one example—may have lied under oath in ways that would be relevant to Mueller and could subject them to possible perjury charges. “Our first order of business is to make sure that Mueller has the benefit of the work that we’ve done,” Schiff said, “so that he can view that evidence in the context of what he knows, which is far more than we do. But also so that he can determine whether people committed perjury before our committee.” Schiff said he wanted to recall Bannon because he simply refused to answer key questions when Republicans controlled the panel, not even bothering to cite a valid legal reason for his refusal beyond the White House’s request. And Trump’s former attorney Michael Cohen could have valuable additional information, given that his first testimony to the Hill panel occurred before he broke with the President and agreed to coöperate with Mueller. “We’d be very interested in talking to him again,” Schiff said.

Mueller and the Russiagate allegations are hardly the only matters that should concern Trump. The new Democratic-controlled House is likely to investigate dozens of other scandals of the Trump era that the Republican majority has simply averted its gaze from; the Web site Axios has published a list of at least eighty-five different allegations and subjects that might soon be the subject of hearings and subpoenas. Schiff is not the only incoming chairman eager to investigate. I asked Schiff, for example, about the enduring mystery of Trump’s private one-one-one meeting with the Russian President, Vladimir Putin, in Helsinki this summer, and whether his panel would try to uncover what had happened in it. Schiff said he wanted to look into it, but so did the House Foreign Affairs Committee. The Democratic leader Nancy Pelosi will have to adjudicate such disputes; I predict there will be many.

No matter which committee is issuing the subpoenas, there is little doubt that Trump will choose a course of maximum confrontation, betting on the Republican-controlled Senate to be his bulwark against the Democrats. “We have to expect based on the President’s track record, based on how he’s dealt with the Mueller investigation,” Schiff told me, “that his response to any oversight, no matter how legitimate, will be to personally trash anyone involved in it, will be to attack in every way, and, given the new bevy of lawyers he’s hired, to stonewall.” Seems like the safest of safe bets.