A House Intelligence Committee hearing on Monday produced the remarkable spectacle of FBI director James Comey publicly testifying that there was “no information that supports” tweets by Donald Trump alleging wiretapping of his New York headquarters on the order of Barack Obama.

It saw National Security Agency director Michael Rogers agree with the British Government that it was “utterly ridiculous” for the White House to suggest that such surveillance had been undertaken by Britain’s signals agency. And it produced official confirmation by Comey that the agency is investigating Russia’s interference in the US presidential election, including possible co-ordination with members of the Trump campaign.

You would think that all of this would be of surpassing concern for Republican members of Congress. The President who leads their party has been officially reported to have made false statements alleging criminal activity by his predecessor. What is more, his campaign is under scrutiny for possible co-operation with a dedicated and dangerous US adversary to subvert American democracy.

Yet, to listen to Republican members of the Intelligence Committee, the most pressing problem to arise from Russia’s intervention and the FBI’s investigation of it is that reports of contacts between Russia’s ambassador and Trump’s designated national security adviser were leaked to The Washington Post. The priority of chairman Devin Nunes and other Republican members, judging from their statements, is not fully uncovering Russia’s actions but finding and punishing those who allowed the public to learn about them.

Nunes and Trey Gowdy, of South Carolina, could not have been more zealous in their outrage over the exposure of Michael Flynn, who was forced to resign as national security adviser after reports in The Post exposed his lies about his conversations with Russian Ambassador Sergey Kislyak. Flynn accepted nearly $68,000 in payments from Russian companies, including the state propaganda outlet, before advocating greater co-operation with Moscow during his brief White House stint. Yet Nunes and Gowdy would have it that hunting down the sources for the disclosure that Flynn discussed the lifting of US sanctions with Kislyak is more urgent than learning the full extent of the contacts he and other Trump aides had with Moscow.

The Republicans seem to be slavishly following the cues of the President, who, while failing to retract his accusation against Obama, is seeking to direct attention elsewhere. “The real story that Congress, the FBI and all others should be looking into is the leaking of classified information,” he tweeted on Monday morning. Such a diversion, like anything else that distracts attention from Vladimir Putin’s support for his election, would be to Trump’s advantage.

Congressional Republicans ought to consider larger national interests. Russia’s intervention in the election was not incidental and haphazard, but part of a concerted campaign to disrupt Western democracy. Putin is even now attempting to interfere in live election campaigns in France and Germany. Given Trump’s refusal to acknowledge the threat, it is essential that Congress discover the truth about Russia’s activities, take steps to defend against similar intrusions in the future and help allies protect themselves.

The first useful step would be to fully inform the public. Instead, Nunes and his followers appear bent on silencing anyone who would do so.