It is strange to think that even as we approach the 20th anniversary of the Sept. 11 attacks, some two decades later we’re consumed with sorting through another nationally traumatic and transformative attack on the country — the Jan. 6 insurrection attempt by supporters of Donald Trump.

In the wake of the 2001 attacks on the Twin Towers and the Pentagon, the nation undertook a bipartisan effort at an accounting and a reckoning. That gave rise to the 9/11 Commission and its subsequent report, which totaled hundreds of pages of often riveting, wrenching reading.

Now, as then, we’re embarking on another such reckoning. Only this time, it’s being conducted largely by Democrats on the Jan. 6 select committee, as Republicans mostly sit the proceedings out. But what, exactly, should the committee investigate? What would a real reckoning look like?

I talked to Richard Ben-Veniste, a veteran D.C. lawyer who served on the 9/11 Commission and is well positioned to help answer that question. An edited and condensed version of our conversation follows.

Greg Sargent: What are the main differences between the Sept. 11 investigation and the Jan. 6 investigation?

Richard Ben-Veniste: As grievous as was the blow we suffered on 9/11 in immediate loss of life and longer-term repercussions, [Osama] bin Laden and his cohort of foreign enemies never posed an existential threat to our survival as a constitutional democracy.

When viewed in the context of the motives of its perpetrators, the Jan. 6 attack on the Capitol, fomented and executed by Americans, poses a potentially more sinister threat than we faced on 9/11.

Sargent: Isn’t one thing that has to be established here how concerted the plot to overturn the election really was?

Ben-Veniste: The select committee must probe the origins of the “Stop the Steal” disinformation campaign. In doing so, there are a number of threads it must investigate, to determine whether they constitute a body of evidence that, together, is far more insidious than the horrendous activities of the mob on Jan. 6.

Sargent: It seems to me the committee needs to determine to what degree Trump envisioned an actual coup. He obviously intended the mob to interrupt the transfer of power. Would you look at what his broader endgame was?

Ben-Veniste: Certainly the select committee has to look not only to the acts themselves but to the intentions behind them. For example, the committee must investigate the president’s attempt to persuade Vice President [Mike] Pence to violate his duty to certify the electoral college vote.

Sargent: The select committee has directed the Department of Justice to turn over any documents relating to discussions about Pence’s role in counting electoral college votes.

Doesn’t that indicate the committee is looking to establish whether Trump tried to corrupt DOJ into creating a fake legal theory for Pence to work from in subverting the vote?

Ben-Veniste: There are a variety of different aspects of the attempt to influence the Department of Justice that would be appropriate areas of inquiry.

Sargent: It’s also telling that Pence reportedly refused to get into his armored car in a secure place below the Capitol, after he had been removed. What lines of inquiry does that suggest?

Ben-Veniste: To his great credit, the vice president reportedly resisted the notion that he be taken from the Capitol, and instead insisted that he remain available to resume his responsibility when it was cleared of the mob.

Sargent: Doesn’t that suggest the committee should try to determine whether Pence had some sense of what the consequences of being removed might be, and whether Pence believed that Trump and his co-conspirators wanted him removed for the purposes of their broader effort?

Ben-Veniste: If there’s any specific information related to that, it would be relevant. The belief of the vice president seems to have been that he needed to stay where he was.

Sargent: There was a vehemence to it, as if he understood what was being tried.

Ben-Veniste: Remember, the reporting suggests that every sort of method had been used by the president to try to get Pence to avoid doing his constitutional duty. He was humiliated, threatened, cajoled.

Sargent: What about the military figures who wrote the joint op-ed piece reminding everyone that the military couldn’t get involved in the election?

Ben-Veniste: All 10 living former secretaries of defense wrote [an op-ed in] The Washington Post stating their view that any effort to involve the military in election disputes would take the nation into dangerous and unconstitutional territory.

I think it behooves the investigators to determine what these individuals were hearing from their networks about any attempt to utilize the military through the invocation of martial law, or the Insurrection Act, which we know various individuals close to Trump were advocating to the president.

Sargent: The committee should seek to determine whether they had concrete reasons for issuing that warning?

Ben-Veniste: Were they hearing things that the investigators should look into?

In addition to the mob violence in the Capitol, what if there had been a response by counterdemonstrators? Violence in the streets of Washington, ready-made for TV, would add to any argument that the Insurrection Act or federalizing the police and other law enforcement agencies would be an appropriate reaction to the violence.

Sargent: It sounds like you think the committee should determine whether there was a concerted plot to stoke violence, potentially to trigger a counter-response, creating even more bedlam — which in turn could be used to postpone the count, particularly if they had accomplished the other piece of the puzzle, which would have been to get Pence off the premises.

Ben-Veniste: All elements that would lead to the interruption of the democratic process should be the subject of the investigation. You can’t look at simply the mayhem and murder committed on Jan. 6 in a vacuum.

Sargent: What it all adds up to is, how did all these pieces fit together, and to what degree was there a genuine plot to prevent a legitimately elected government from taking over in order to keep Trump in power illegitimately?

Ben-Veniste: Connecting the dots, as it were, is the proper function of the investigators.

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Conspiracy theories blaming George W. Bush for the Sept. 11, 2001, terrorist attacks have been debunked, yet millions of Americans still believe them. (Kate Woodsome, David Byler/The Washington Post)