It was a coup against Trump
"When the group arrived at the perimeter, they did not act like any group of protestors I had ever seen. Unlike other heated protests, these protesters did not simply congregate to angrily voice their grievances.
As soon as this group arrived at our perimeter, they immediately began to fight violently with the officers and to tear apart the steel crowd control barriers, using them to assault the officers.
It was immediately clear that their primary goal was to defeat our perimeter as quickly as possible and to get past the police line. This mob was like nothing I have seen in my law enforcement career.
The group consisted of thousands of well-coordinated, well-equipped violent criminals. They had weapons, chemical munitions, protective equipment, explosives, and climbing gear. A number of them were wearing radio ear pieces indicating a high level of coordination."
Sounds like Antifa, not the typical pro-Trumper