There is a lot of unauthorized video of the coverage of 9/11 from all the news services, so it’s good to find an original set of films owned by one of the networks. Here is CNN’s own link ("Inside 9/11: The Day that Never Ends"), which shows that at first, people inside the North Tower had no real idea of what had happened.
CNN’s original coverage is curious. It took about four minutes for the newscaster to realize a separate second plane had hit the South Tower. And for a little while there was speculation about a “navigation error” rather than acceptance of terrorism. Most other networks immediately said that a second plane attack implied terrorism.
Donald Trump’s own reaction on 9/11 is in this video.
I was in my apartment in Minneapolis for about 15 minutes during the aftermath and saw the South Tower fall on ABC.
Update: April 27
CNN tonight aired the one-hour "Soundtracks: The Songs that Defined History" about the music world after 9/11. Tribeca showed it (notes).