September 11, 2001 is one of those days where everyone remembers exactly where they were.
It was, of course, the date when terrorists hijacked aircraft and crashed them into both the World Trade Center in New York City. Others hijacked a third plane and flew it into the Pentagon in Washington, D.C., while a fourth crashed in a field near Shanksville, Pennsylvania after passengers rose up against their terrorist captors.
The events instantly defined an entire generation of Americans as "our Pearl Harbor," and the day consumed the world around everyone who watched it unfold on live television.