But how we think of these events determines how we respond. And even in the case of 9/11, when we had every right to pursue justice and preventive reforms, not everything we did in the ensuing weeks and months was good: a war in Afghanistan that has gone on too long, a war in Iraq that should never have been waged in the first place, the torture and indefinite detention of suspects with questionable evidentiary standards and worse treatment, mass warrantless surveillance of Americans of all backgrounds and discrimination against Muslims.

Without adequate safeguards, the reaction to Jan. 6 is even more ripe for overreach. We are dealing with a mainly domestic set of people in an era of extreme partisan polarization. We are unlikely to go to war over the Capitol riot, but we may increase our surveillance of American citizens and ensnare a lot of ordinary people who subscribe to widely held views. Some progressives have already raised these concerns.

People have the right to believe eccentric, even factually wrong things as long as they behave peacefully. The rioters who laid siege to the Capitol did not behave this way, but many septuagenarians posting pro-Trump memes on social media do, even if they also espouse unfounded claims about the 2020 election.