On Donald Trump’s inauguration day in 2017, I watched dozens of Capitol Police officers in riot gear repeatedly charge young people engaged in nonviolent civil disobedience on a public street many blocks from the Capitol. Members of the National Guard looked on from beside armored vehicles.

The police mobilization that day was enormous, and not only among the Capitol Police. More than three thousand officers from dozens of agencies and five thousand members of the National Guard were on alert in DC. For all that, the worst “violence” happened almost two miles from the ceremonies, when some store windows got smashed up and a handful of garbage cans were set on fire.

The police response to the inauguration was a sharp contrast to the events of January 6, 2021. As we saw on live TV, Trump supporters not only broke into the Capitol during a constitutionally mandated event but came within feet of seizing Vice President Mike Pence, who they were threatening to hang. They entered congressional chambers with guns and zip ties, planning to detain members of Congress; some of them stole Nancy Pelosi’s computer. Short of members of Congress actually getting killed, which by all accounts was a real though unrealized possibility, it’s hard to imagine a greater law enforcement failure.