Last year on Jan. 3, an internal Capitol Police intelligence report warned that Congress could be targeted by a mob of Trump supporters in the coming days. Later that day, then-U.S. Capitol Police Chief Steven Sund began to worry about the growing number of protestors expected to attend the "Stop the Steal" rally.Most of us know what happened next.The morning of Jan. 6, Trump supporters migrated towards the White House. Then-President Donald Trump gave a speech in which he repeated false claims about a stolen election and urged his supporters to march to the Capitol where Congress was confirming Joe Biden's victory.They did. Thousands of them.A year later, many of us are still trying to understand what went wrong in the immediate response to the Jan. 6 riot — and what's been done to make sure another attack won't happen.Want to support 1A? Give to your local public radio station and subscribe to this podcast. Have questions? Find us on Twitter @1A.