Inside the Insurrection on Congress:

Most of the videos we analyzed were filmed by the rioters. By carefully listening to the unfiltered chatter within the crowd, we found a clear feedback loop between President Trump and his supporters.

As Mr. Trump spoke near the White House, supporters who had already gathered at the Capitol building hoping to disrupt the certification responded. Hearing his message to “walk down to the Capitol,” they interpreted it as the president sending reinforcements. “There’s about a million people on their way now,” we heard a man in the crowd say, as Mr. Trump’s speech played from a loudspeaker.