Is it possible to talk of political theatre when the star of the show refuses to take centre stage? The special counsel Robert Mueller was obliged to come to Capitol Hill on Wednesday by a subpoena, and made his distaste plain on arrival. His reluctance underscored the unlikelihood of great revelations emerging from his testimony to the house judiciary and intelligence committees on potential obstruction of justice, and election meddling by the Russians. He hoped that his 448-page report would speak for itself, even after Donald Trump’s attorney general had misspoken on its behalf.

So the hearings were not about discovering new material, but about deploying the existing facts: the Democrats, seeking compelling soundbites that might help to rouse the public and rally them behind the party; the Republicans, seeking to damage the credibility of the investigation itself as biased, unfair and even un-American. The inherent implausibility of claiming simultaneously that the inquiry was a partisan witch-hunt, and that it exonerated Mr Trump, go unaddressed.

Mr Mueller’s initial statement stressed the impartiality and integrity of his team. He pushed back against Republican attacks upon its composition. Addressing the question of obstruction of justice, he seemed less like Mr Trump’s nemesis than his antithesis: sober and tight-lipped, repeatedly returning to yeses and noes and the same non-answers.

Yet the facts of the report are telling and Mr Mueller spelled at least some of them out. He contradicted Mr Trump’s claims of exoneration: “The president was not exculpated for the acts that he allegedly committed.” He confirmed (contradicting the attorney general William Barr) that he had not reached a decision on indicting Mr Trump because of the Office of Legal Counsel’s opinion that indicting a sitting president would be unconstitutional. He stated that the president could be charged with obstruction of justice after leaving office.

He saved his indignation for the second hearing. His report had made clear the scale of the Russian attack on US democracy and how the Trump 2016 campaign embraced a foreign adversary’s help, made use of it, and then covered it up. Now he described the document as a flag warning people not to let it happen again.“I hope this is not the new normal, but I fear it is,” he added, when asked whether future campaigns could accept foreign interference.

His appearance is unlikely to transform public attitudes, still less to resolve the Democrats’ struggle over whether to impeach the US president. The Republicans remain squarely behind a man so signally unfit for office, and appear less troubled by foreign interference than by the inquiry into it. All this is part of the process by which Congress holds the president accountable. How far that process goes is the question which Democrats must now answer. A still more urgent issue is how to make sure the US is protected from further election meddling as 2020 approaches.