Why did #J6 ers become agitated and aggressive? No, it was not because "we didn't get our way" with the Joint Session of Congress and then wanted to "take over the Federal Government". 

People became pissed when Capitol Police began employing riot measures on a peaceful protestors.

We all witnessed the #BLM riots during the 2020 "Summer of Love". Each riot developed the same way: A daytime peaceful protest followed by riots as the sun went down. You could watch the news and each reporters would continously discuss about "when will police  declare the event to be an unlawful assembly?". This would come as an announcement on loud speakers to the crowd. "This is an  unlawful assembly and you are ordered to disperse. Those remaining will be subject to arrest." This was always followed by statement warning of the riot measures to be employed.

No such declaration and warning was ever announced to #J6 ers who were at what they believed to be the area of a permitted second event.

We were attacked with no warning. Tear gas, flash bangs, and rubber bullets were shot into a peaceful crowd of unarmed protestors. It was chaos.
#J6