“While this report does not conclude that the President committed a crime, it also does not exonerate him.”

Such is the key, complicating sentence in Attorney General William Barr’s four-page summary of the “principal conclusions” of Robert Mueller’s twenty-two-month investigation, which he issued to Congress on Sunday afternoon.

Barr, who took office as Attorney General last month, writes that Mueller, the special counsel, determined that no one associated with the Trump campaign conspired with the Russians in what all the leading intelligence agencies have determined was a concerted effort to manipulate the 2016 election to hurt Hillary Clinton and help Donald Trump.

Although the Attorney General used the phrase “does not exonerate him” on the question of obstruction, the President refused any such complication, tweeting, “No Collusion, No Obstruction, Complete and Total EXONERATION. KEEP AMERICA GREAT!” Speaking on the tarmac in Florida, before flying back to Washington, Trump vented his resentment, calling the investigation an “illegal takedown that failed.”

“After a long investigation, after so many people have been so badly hurt, after not looking at the other side, where a lot of bad things happened, a lot of horrible things happened, a lot of very bad things happened for our country, it was just announced there was no collusion with Russia, the most ridiculous thing I’ve ever heard,” he said. “There was no collusion with Russia. There was no obstruction, and none whatsoever, and it was a complete and total exoneration. It’s a shame that our country had to go through this. To be honest, it’s a shame that your President has had to go through this; before I even got elected, it began. And it began illegally! And hopefully someone’s going to look at the other side. This was an illegal takedown that failed.”

It is on the question of obstruction of justice that the political battle will, inevitably, continue. Barr writes that, on this score, the Department of Justice “determined not to make a traditional prosecutorial judgment”—which means, as Jerrold Nadler, the chairman of the House Judiciary Committee put it, it “seems like the Department of Justice is putting matters squarely in Congress’ court.”

Nadler made it plain that the conclusion of the Mueller report will not lead to a cessation of investigations into the President’s activities. Appearing on “Fox News Sunday,” Nadler said, “The job of Congress is much broader than the job of special counsel.” He explained that Mueller’s role was to find criminal action. The various House committees, he said, “have to look for abuses of power. We have to look for obstruction of justice. We have to look for corruption.” Today’s four-page document is only a brief summary of Mueller’s report, as written by the Attorney General. If Barr decides not to release the full report, congressional Democrats will almost certainly fight the decision in the courts.

It’s hardly as if Mueller found no wrongdoing. He issued nearly two hundred charges, against thirty-four people, including Trump’s first national-security adviser, Michael Flynn, his campaign chairman Paul Manafort, and one of his lawyers, Michael Cohen. Mueller led a team of nineteen lawyers and forty F.B.I. agents, along with forensic accountants and intelligence analysts. He issued twenty-eight hundred subpoenas and five hundred search warrants. A registered Republican with a reputation in official Washington as a person of competence and integrity, Mueller never answered Trump’s repeated charges that the investigation was a “witch hunt” or news reports that the President wanted to put a premature end to his efforts.

When the news came, Friday evening, that Mueller would not issue any further indictments, there was relief and celebration at the Mar-a-Lago Club, where Trump and his family were spending the weekend. The President celebrated his son’s thirteenth-birthday dinner on the patio and, following the advice of his lawyers and advisers, resisted the impulse to repeat last week’s Twitter barrage. Then he went inside, to the ballroom, for a fund-raiser, where there was chanting, once again, for the incarceration of Hillary Clinton. (“Lock her up! Lock her up!”) On Sunday morning, Trump kept his cool once more, tweeting, “Good Morning, have a Great Day!”

From the start, Trump has declared the Mueller investigation unfair, a fraud, a partisan effort intended to derail his Presidency. Now it is likely that he will aim similar attacks at committees in the House of Representatives and various state and federal courts, particularly in New York, that are investigating Trump’s business practices, his charities, hush-money payments, the irregular issuance of security clearances, and other matters. The President will soon be deposed in a defamation case brought by a woman who appeared on his reality-television show and charges that he groped her.

Steve Bannon, the strategist and ideologist who was instrumental in Trump’s campaign victory, hinted broadly at what might be next. In a telegraphic e-mail to the Washington Post, he said that Trump would “weaponize Mueller report to bludgeon Democrats. Expect him to ‘come off the chain.’ ”

In fairness, Bannon went on CBS a month ago and used similarly melodramatic language in an entirely different direction. He said that, now that the Democrats controlled the House, “they could weaponize the Mueller report.” He added, “I think that 2019 is going to be the most vitriolic year in American politics since before the Civil War. And I include Vietnam in that.”

Adam Schiff, the chairman of the House Intelligence Committee, insisted that, despite Mueller’s conclusions, Trump should not be let off the hook on the matter of collusion. On Sunday morning, he told George Stephanopolos, of ABC, “There’s a difference between compelling evidence of collusion and whether the special counsel concludes that he can prove beyond a reasonable doubt the criminal charge of conspiracy.”

Schiff continued, “I leave that decision to Bob Mueller, and I have full confidence in him . . . But that doesn’t mean, of course, that there isn’t compelling and incriminating evidence that should be shared with the American people.”

Schiff said that it was a “mistake” for Mueller not to have interviewed the President face to face and to have accepted, instead, written responses to a series of questions. “I can certainly understand why the lawyers, like [Rudy] Giuliani, were fighting this, because the President is someone who seems pathologically incapable of telling the truth for long periods of time. But, nonetheless, if you really do want the truth, you need to put people under oath, and that should have been done.”

Donald Trump, Jr., who has often acted as a kind of even-higher-volume version of his father on social media, reacted sarcastically to Schiff’s comments, saying on Twitter, “He should really show it to us then. Maybe he got it from the Ukrainian shock jocks that pranked him like the clown he is. How is this hack in charge of The House ‘Intelligence’ Committee? What a joke.”

Speaker of the House Nancy Pelosi has said that her party should not press for impeachment; her fear is that the issue would be too divisive during a Presidential political campaign and that the effort will inevitably fail in the Senate. On MSNBC, Joy Reid asked John Lewis, a House Democrat from Georgia and a leader in the civil-rights movement, about the possibility of impeachment. Lewis said, “I think that day will come. I don’t think he’s legitimate. I said it back at the end of the election. I still believe that today.”