“Luck may be needed in the Second Civil War,” Larry Rendell Brock Jr., a Texas man charged in connection with the attack, wrote on Facebook in the days before the events in Washington, according to federal prosecutors. Mr. Brock had aspired to take hostages, prosecutors said, and tagged the post with the names of two antigovernment groups.
At least two prominent activists involved in the 2017 Charlottesville rally were also at the Capitol riots, according to Amy Spitalnick, the executive director of Integrity First for America, a nonprofit group underwriting a lawsuit over the violence in Charlottesville.
One of them was Nicholas J. Fuentes, 22, a far-right agitator whose online diatribes in support of white nationalism and attacks against Jews and L.G.B.T. people have attracted a significant following among college students. His followers, waving flags bearing the logo of his America First organization, were seen storming the Capitol. Mr. Fuentes, in a video, praised the assault for being more brazen than any Black Lives Matter or antifascist protest, though he appears to have stayed outside.
“We forced a joint session of Congress and the vice president to evacuate because Trump supporters were banging down and then successfully burst through the doors,” he exclaimed.
Lindsay Schubiner, a program director at the Western States Center focused on countering white nationalism, said it has been frightening to watch the rise of far-right groups in recent years who pose dangers to people of color and L.G.B.T.Q. communities. Without a major disruption, she expects the extremist groups to remain a risk to public safety and to the nation’s democracy for years to come.
“This isn’t something that can be put back in the bottle — at least not quickly or easily,” Ms. Schubiner said.
The attack on the Capitol was likely to become “a significant driver of violence for a diverse set of domestic violent extremists,” an array of government agencies said in a joint intelligence bulletin issued on Jan. 13. The storming of the building, several analysts said, could fuel a dangerous pushback against the incoming Biden administration and its agenda on gun control, racial justice, public lands and other issues by extremists who are not afraid to use violence to get their way.