A violent mob of President Donald Trump's supporters invaded the U.S. Capitol on January 6, as Congress met to certify Joe Biden as the 46th president of the United States. The rioters plotted for weeks beforehand on social media, mobilizing around the president's false claims of a stolen election. 

Who are the forces behind the attack, how did it unfold and why was the law enforcement presence so easily overpowered?

ProPublica reporter and FRONTLINE correspondent A.C. Thompson, who covered the rise of right-wing extremism for our joint "Documenting Hate" series, joins The FRONTLINE Dispatch to discuss what happened at the Capitol and what the future may hold.

Thompson’s reporting is part of an ongoing collaboration between ProPublica and FRONTLINE that includes an upcoming documentary.