Framing his diplomatic visit to Europe within a broader historical mission, President Joe Biden rightly warns us that authoritarians are eager for democracy to fail. He knows very well that democracy's enemies are active here as well as abroad. Now, he and the leadership of his party must act to fully expose the most overt assault on our system of self-government since the Nixon era.

Congressional Democrats should move swiftly, with Biden's support, to establish a select committee to investigate the January 6 insurrection.

Like many Americans, including Democrats, Republicans, and independents, the president previously expressed his preference for an independent bipartisan commission, empowered by Congressional legislation, to conduct that investigation. But that path was closed last month when Senate Republicans killed the January 6 commission bill that had already passed the House. They did so at the bidding of Donald Trump, the principal investigative target, and of Senate Minority Leader Mitch McConnell, who articulated one of their more absurd arguments against the commission.

"I think we will know everything we need to know. We were all witnesses," he said. "We were right there when it happened and I simply think the commission is not necessary." When a shattering crime occurs and a major witness then insists that an investigation is "not necessary," suspicion immediately arises concerning that person's consciousness of guilt.

The devious McConnell has aimed to prevent or discredit an investigation of January 6 not because we "know everything we need to know," but because he's scared to death of what we will learn — about the former president and other members of their party. On Trump's orders, the minority leader instructed his caucus to vote down the commission, despite its perfectly bipartisan composition, its pre-midterm deadline and a host of other features demanded by House Republicans.

Of course, this isn't the first time that Republicans have tried to evade scrutiny of a national catastrophe for which they were culpable. The bill establishing a commission to investigate January 6 was modeled on the 9/11 Commission — but that probe itself was nearly killed by aides to President George W. Bush, who feared that he would be blamed for failing to curtail the al-Qaida plot.

Then-Vice President Dick Cheney made a threatening phone call in the spring of 2002 to Senator Tom Daschle, the Democratic majority leader, warning that any investigation of 9/11 would be seen as a partisan maneuver and a hindrance to the "war on terror." Cheney's intervention is ironic in hindsight since his daughter Liz is among the handful of Republicans who urge a thorough investigation of the Capitol insurrection.

Congress ignored Cheney's whining; Bush reluctantly signed the enabling legislation; and the 9/11 Commission discharged its duties honorably, issuing a report that escaped the "partisan" taint. Now, however, the Republicans have only themselves to blame for shutting down the option of an independent commission on which they would have shared equal authority with Democrats.

Instead, House Speaker Nancy Pelosi can and should create a select committee to investigate the events of January 6. With the House Republicans behaving as if nothing untoward happened that day, the select committee ought to operate with a Democratic majority and a tough chair who will dismiss obstruction and distraction from the minority. And unlike the commission that Republicans stupidly killed, it would have the power to issue subpoenas without their consent.

No doubt some Democrats in Congress, as well as the White House, fear that any investigation of January 6 will suffer from accusations of partisanship. In a moment of comical hypocrisy, Minority Leader Kevin McCarthy — who boasted about the partisan gains achieved by the Benghazi select committee in 2015 — has already leveled that charge against the bipartisan commission. Republicans are never more indignant than when they're faking it.

But who cares what McCarthy thinks anyway? What will matter in this investigation is an orderly, comprehensive, and undaunted finding of facts. It is indeed possible that such an investigation will benefit Democrats in the midterm elections and beyond. That's why Republicans want to stop it at all costs.

Too bad for them. Unearthing the truth about a violent assault on our Constitutional procedures — nothing less than an attempted coup d'etat — is a fundamental duty of Congress that cannot be evaded. Tempted by authoritarianism, the Republicans have chosen to dishonor their oath and cover up a crime against our country. There must be consequences for that, or we will forfeit our democratic heritage, perhaps forever.

To find out more about Joe Conason and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.