WASHINGTON – Special counsel Robert Mueller, whose investigation in large part has defined the first half of President Trump's tenure, was spied in front of the White House on Sunday morning as he and his wife walked across Lafayette Square toward St. John's Episcopal Church.

The former FBI director looked, finally, relaxed.

That wasn't exactly the impact his long-awaited and confidential report had on the rest of official Washington. On a balmy spring Sunday, as Attorney General William Barr delivered the "principal conclusions" of the report to Congress, Republicans declared the president vindicated, and some Democrats found themselves on the defensive.

To be clear, only a summary of Mueller's report, and none of his inquiry's underlying evidence, was released. What's more, federal and state investigations into the president's business organization, his charitable foundation, his payment of hush money during the campaign and his inaugural committee are continuing and could lead to legal troubles down the road.

Even so, Mueller's report, nearly two years in the making, shifted the political landscape.

"The investigation did not establish that members of the Trump Campaign conspired or coordinated with the Russian government in its election interference activities," Mueller's report concluded, according to Barr. But the special counsel said he couldn't reach a conclusion on the question of obstruction of justice: "While this report does not conclude that the President committed a crime, it also does not exonerate him."

Mueller referred that issue to the attorney general. After consulting with other Justice Department officials, Barr said he concluded that the special counsel's investigation wasn't sufficient "to establish that the President committed an obstruction-of-justice offense."

"It was a complete and total exoneration," Trump told reporters just before he boarded Air Force One to return to Washington from his Mar-a-Lago resort in Florida. "No collusion, no obstruction."

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Actually, it might not sound like glowing endorsement of the president's behavior. But it means Mueller didn't indict anyone named Trump, neither the president nor his children. He didn't charge Trump or his associates of conspiring with Moscow to meddle in the 2016 election – the question at the core of Mueller's mission. And his boss, the attorney general, concluded that the president shouldn't be indicted for obstruction.

That overshadowed the indictments, the plea deals and the convictions that Mueller did secure in the most far-reaching exposure of wrongdoing around a president since Watergate. Those accused of crimes or pleading guilty to them include those who had served Trump as campaign chairman, deputy campaign chairman, national security adviser, longtime political adviser and personal lawyer-and-fixer. The special counsel showed that Russians interfered in the election to help Trump, and that the Trump team was open to benefiting from their help. Several of his aides were charged with lying about what they had done.

But the political world and the president himself have focused on the two most serious potential offenses, of collusion and obstruction. Those were charges Mueller didn't make.

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The report's conclusions make it less likely that congressional Democrats will move to impeach the president. House Speaker Nancy Pelosi has said she's opposed to considering Articles of Impeachment – a cause advocated by some of the party's loudest progressive voices – unless support for that grave step was "overwhelming and bipartisan."

That standard would require that some Trump voters be persuaded that impeachment was justified, and that it was possible not only that the Democratic-controlled House would impeach Trump but also that the Republican-controlled Senate would convict him.

There was no sign of a bombshell powerful enough to do that.

"This case is closed," House Republican leader Kevin McCarthy of California declared in a statement, a theme the GOP is likely to hammer. "It is time we move on for the good of the nation."

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Through the day, there was some revisionism across the capital in attitudes toward Mueller. Pelosi and other Democratic leaders had used the special counsel's inquiry as a shield, urging their troops to delay discussing impeachment until his report was in hand. Now Intelligence Chairman Adam Schiff, D-Calif., said on ABC's "This Week" that it had been "a mistake" for Mueller to rely on written answers from Trump and not insist on a face-to-face interview with him.

House Judiciary Chairman Jerry Nadler, D-N.Y., insisted that Mueller's report didn't settle the big questions for Congress on impeachment. "What Congress has to do is look at a broader picture," he said on CNN's "State of the Union." Senate Democratic leader Charles Schumer and Pelosi said in a joint statement that it was crucial to release not only the full report but also the underlying evidence. That may require a court battle – for instance, if the president asserts executive privilege to bar some disclosures.

Now, however, it was the GOP wielding Mueller as a shield, arguing that his conclusions meant that additional investigations by Democrats would be a case of partisan overreach. Ohio Rep. Jim Jordan, the ranking Republican on the House Oversight Committee, mocked Democrats for raising questions about the inquiry.

"This is Bob Mueller," Jordan said, someone Democrats had been defending and portraying as "right next to Jesus; he can almost walk on water."

Meanwhile, from Trump, there was no resumption of the stream of tweets denigrating Mueller for conducting a "witch hunt" (a phrase the president had hurled at the special counsel 183 times since his inauguration, according to the Trump Twitter Archive) or a "hoax" being pursued by "13 Angry Democrats" on Mueller's staff.

The president started the day with an unusually sunny tweet. "Good Morning, Have A Great Day," he said. Hours later, he described himself as a victim. "It's a shame that our country had to go through this," he told reporters. "To be honest, it's a shame that your president has had to go through this."

He may have more to say on the subject Thursday in Grand Rapids, Michigan. He's scheduled to address a rally for his 2020 re-election campaign.

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