By the time the mob got to the Capitol steps it was too late for the cops to control them:
The French police official detailed multiple lapses they believe were systematic:
Large crowds of protesters needed to be managed far earlier by the police, who instead controlled a scene at the first demonstration Trump addressed, then ignored the crowd as it streamed toward the Capitol.
"It should have been surrounded, managed, and directed immediately, and that pressure never released."
Because the crowd was not managed and directed, the official said, the protesters were able to congregate unimpeded around the Capitol, where the next major failure took place.
"It is unthinkable there was not a strong police cordon on the outskirts of the complex. Fences and barricades are useless without strong police enforcement. This is when you start making arrests, targeting key people that appear violent, anyone who attacks an officer, anyone who breaches the barricade. You have to show that crossing the line will fail and end in arrest."
"I cannot believe the failure to establish a proper cordon was a mistake. These are very skilled police officials, but they are federal, and that means they ultimately report to the president. This needs to be investigated."
"When the crowd reached the steps of the building, the situation was over. The police are there to protect the building from terrorist attacks and crime, not a battalion of infantry. That had to be managed from hundreds of meters away unless the police were willing to completely open fire, and I can respect why they were not."