Democrats had hoped that with the long-awaited testimony of former special counsel Robert Mueller III, they would finally have a clarifying, cinematic moment, perhaps one that would convince a reluctant public to rally behind impeaching President Donald Trump.

The idea was that if people could only hear the conclusions of his 22-month investigation through the lips of one of nation's most distinguished public servants, it would come to life.

As countless pundits put it in recent weeks, Americans needed to "see the movie." Hours of back-and-forth across a witness table could produce clips that would play in a loop on cable news and over social media, penetrating the public consciousness in a way that a 400-plus-page report could not.

It did not happen.

Instead of the "Saturday Night Live" Robert De Niro version of Mueller, with a little bit of Atticus Finch thrown in, the real-life prosecutor was not a made-for-television witness. He did what he said he would, which was stay within the redacted confines of what his team had written.

At many points during the day of testimony, Mueller, 74, struggled to do even that. He often seemed to lack a grasp of the massive amount of material in the report - perhaps evidence of how uncomfortable the former FBI director was in that hyperpartisan environment.

Democrats on the Judiciary and Intelligence committees, by and large, did a credible job of keeping their questions focused. They had some good moments, many of which came as Mueller set the record straight on the many lies that Trump has told about the conclusions of the report.

No, he said, it did not "exonerate" the president of the crime of obstruction, for which Trump could still be prosecuted after he is out of office.

And former White House counsel Donald McGahn, whose FBI interviews provided some of the report's most damning evidence, is not the fabulist that Trump has portrayed him to be, but a credible witness, Mueller said - which no doubt will increase pressure on McGahn to also take a turn before the House Judiciary Committee.

Mueller also batted down the president's claims that he has been the victim of "a hoax" that Russia interfered in the 2016 election on Trump's behalf, and that the special counsel's investigation was nothing more than "a witch hunt." He furthermore described Trump as having been "generally" untruthful in sworn answers to written questions put to him during the special counsel's investigation.

But the fact that the president dissembles without shame is hardly news to the American public. And at times, Mueller's terse responses to lawmakers' queries created confusion.

In one exchange that created a brief buzz, Mueller responded in the affirmative when Rep. Ted Lieu, D-Calif., asked whether the reason he "did not indict Donald Trump is because of [Justice Department guidance] stating that you cannot indict a sitting president." Mueller subsequently corrected the impression that he might otherwise have done so, and clarified, as his report did: "We did not reach a determination as to whether the president committed a crime."

House Speaker Nancy Pelosi, D-Calif., has said many times — wisely, in my view — that the House should not move forward on impeachment without significant bipartisan support, and lacking evidence of presidential transgressions so overwhelming that they would win wide acceptance as constituting "high crimes and misdemeanors." Absent those, impeachment would surely end with Trump's acquittal in the Senate and potentially help him win a second term.

Public opinion supports Pelosi on that. In Post-ABC News polling this month, 59 percent said the House should not begin impeachment proceedings.

But to focus on Trump, and whether his actions constitute impeachable offenses, is to miss the real bombshell in Mueller's testimony - the scandal that could be unfolding right there in front of us.

That was Mueller's warning that what happened in 2016 could happen again. Asked by Rep. Will Hurd, R-Texas, whether Russia might be planning another attack on the integrity of U.S. elections, Mueller replied: "They're doing it as we sit here, and they expect to do it in the next campaign." He said "many more countries" are developing the capability to do so as well.

"I hope this is not the new normal," Mueller added, "but I fear it is."

There is a good chance that Wednesday's testimony marked the last time we will ever hear the former special counsel say anything on the subject in public. The message he wanted to deliver was that in wrestling with the problematic past, we should not take our sights off a treacherous future. While that may not have made for electrifying television, Mueller delivered the goods.

Karen Tumulty is a Washington Post columnist covering national politics.