Without 9/11 and with the War on Terror being pushed back three years, drone technology probably wouldn't be as advance as it is today sense as you said, there won't be as big of a need for it.
One thing I could possibly see in a world without 9/11 is that the USA might switch to HDTV before 2009. I heard a while back that 9/11 was a reason why it took until 2009 for the US to switch from SD to HD for television, but it might just be a rumor.
Yes considering the quality of videos back then were 480p highest at best. Especially when I watch old YouTube videos dating back to the 2006-2008.I was intrigued by this so I looked it up and Wikipedia actually has something on this! Under the Problems section they say this,
“New York City-Newark was one of the early U.S. terrestrial digital television pioneers with state-of-the-art ATSC facilities installed atop the World Trade Center as early as 1998, but those facilities were destroyed in the September 11 attacks, and for a number of years, New York lacked one single point of sufficient height from which to cover the entire region without severe multipath interferenceissues in downtown Manhattan.”