WASHINGTON — Since he was first appointed special counsel, Robert Mueller has been a unique foil for President Donald Trump — the kind who doesn't clap back on Twitter, issue press releases in his own defense or go on television to accuse the president of committing crimes.

That may or may not change Wednesday, when Mueller testifies before the House Judiciary and Intelligence committees about the findings of his report on Russian interference in the 2016 election, contacts between Russia and the Trump campaign, and evidence of possible obstruction of justice by the president.

What hasn't changed, though, is Trump's framing of Mueller, his report and his upcoming testimony.

"The report was written — it said 'no collusion,'" Trump said in a message-delivery as predictable as grandstanding at a congressional hearing. "There's no nothing. They're wasting their time."

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He added of Mueller, referring to former FBI Director James Comey, that "there's a lot of conflicts he's got, including the fact that his best friend is Comey," and "he's got conflicts with me, too ... As you know, he wanted the job of the FBI director, he didn't get it, and we had a business relationship where I said 'no,' and I would say that he wasn't happy."

On one level, Trump's two-year campaign to discredit a man he says exonerated him is counterintuitive. There's a version of the world in which Trump simply would have welcomed the news that he wasn't being prosecuted and congratulated Mueller on a job well done. Mueller could have been a hero in Trump lore who stood up to enormous pressure to find criminal wrongdoing.

But the report was never going to be the end of the story, and Trump surely anticipated that Wednesday's public testimony — an airing of what Mueller detailed as the president's encouragement and acceptance of Russian assistance, as well as efforts to block the special counsel's probe — would someday come.

Sean Spicer, former White House communications director under Trump, described the president's messaging on Mueller as an insurance policy in case the special counsel's testimony is more damaging than a report that resulted in no criminal charges against the president.

"I don't think it's a bet," Spicer said. "It's a protection."

If Mueller goes beyond the four corners of the report, Spicer said, Trump will know that he has "already branded this guy as being conflicted."

Indeed, one of the findings that House Democrats are certain to ask Mueller about is Trump's reported effort to pressure then-White House counsel Don McGahn to have Mueller fired over what the president deemed to be a "conflict of interest."

Trump repeatedly has presented as a conflict the consideration of Mueller as a possible successor to Comey, who was fired over the Russia probe (according to Trump in an interview with NBC's Lester Holt) or for his performance investigating 2016 Democratic presidential nominee Hillary Clinton's email scandal (according to then-Attorney General Jeff Sessions and then-Deputy Attorney General Rod Rosenstein). Mueller didn't get the FBI gig, but he did end up running the special counsel probe.

Trump's other beef with Mueller — or Mueller's supposed point of resentment surrounding Trump — stems from Mueller ending his membership at a Trump golf club in 2011.

Rosenstein once testified that he knew of no conflicts that would disqualify Mueller from conducting the investigation.

Still, Trump has kept up an onslaught against Mueller as part of his legal and political strategy throughout the investigation and its aftermath, rallying his supporters to perceive him as the victim of a Democratic and "deep state" government conspiracy bent on undermining his presidency.

That helps explain why Trump has both insisted that he's clean and sought to portray Mueller as dirty.

"If you think that you’re being attacked and you think that there are countless attempts to delegitimize you, then you’re constantly playing a game of both offense and defense," Spicer said.

Trump has tweeted Mueller's name 213 times since December 2017 — including retweets — according to the website www.trumptwitterarchive.com, and "witch hunt," his favorite shorthand for the investigation, 224 times in the same span. Trump frequently talks about Mueller at campaign rallies, and he called the probe a "witch hunt" during a joint press conference with Russian President Vladimir Putin in Helsinki last summer.

Trump went so far as to vouch for Putin's insistence that Russia didn't interfere in the election — an assertion Mueller contradicted in charging Russian nationals and in his report.

"He just said it’s not Russia. I will say this: I don’t see any reason why it would be," Trump said at the time. He later said he meant to say "wouldn't be."

Mueller, on the other hand, has been a largely off-screen presence in his own dramatic play. Aside from reading a statement announcing his resignation in May, Mueller hasn't spoken publicly about the investigation since he was appointed in May 2017.

As part of that statement, he said it would be improper for him to give the testimony he is due to deliver Wednesday at House Democrats' insistence.

"I do not believe it is appropriate for me to speak further about the investigation or to comment on the actions of the Justice Department or Congress," he said.

It remains to be seen whether Mueller will offer any new insights into the meaning of his work — but it would be a surprise if Trump's message on it changes now.