One of the main limitations of the Internet/Web (know the difference!) is that too much of the content becomes lost forever. It sort of comes and goes without so much as a peep; but, shouldn’t we be collecting all of this stuff, just in case?
Somebody is: The Internet Archive. They are collecting the Internet for history. And there are a few other side projects, like the Movie Archive and the 1996 Presidential Election Archive. There is more stuff always being added.
Of particular note should be the Television Archive. As the Web site says, it is a collection “concerning the events of 11 September 2001 — contains television news from around the world.” You can watch the broadcasts, read critical commentary, and see differing perspectives in coverage from television stations worldwide.” If you want to see just the Web activity concerning 9/11, look at their Wayback Machine