By all appearances, Mr. Mueller’s statement did nothing to change Speaker Nancy Pelosi’s calculation that impeachment would hurt the party and the country because Senate Republicans remained unmoved and therefore could block conviction in any Senate trial, where it would require a two-thirds vote to remove Mr. Trump from office.

“It will certainly ratchet up pressure on the Dems to initiate impeachment proceedings, but I don’t think it changes the fundamentals much,” said Jeff Flake, the former Arizona senator who is one of the few prominent Republicans to openly defy Mr. Trump. “It’s still a bad move in terms of 2020, and the speaker knows it.”

At the White House, Mr. Trump watched Mr. Mueller live on television from the residence, where he spent most of the day. He met briefly afterward with a few members of his staff and issued claims of vindication via Twitter and a press statement. But privately he complained that Mr. Mueller had always been out to get him and was peeved that more people were not defending him on television, according to people informed about his day.

Aides said the dominant feeling inside the West Wing was outrage at Mr. Mueller, but they also concluded that the special counsel had not changed the overall dynamics and no special efforts were made to reassure allies on Capitol Hill. No new facts emerged, no smoking gun that had not already been known. Mr. Mueller made clear that he would not go beyond his report even if he was dragged before a congressional committee.

All that happened, as one White House aide put it, was that Mr. Trump’s opponents shook the snow globe and stirred things up.

Rarely has a high-profile special prosecutor left Washington so flummoxed. During Watergate, Leon Jaworski left no doubt about his conclusions regarding President Richard M. Nixon, persuading a grand jury to name him an unindicted co-conspirator before his resignation.