More people have died in the last nine years than that day.
And the length of time of one day is also shorter.
So in what way is one day more than nine years?
More people may have died within 9 years, but in that one day the whole nation watched as two planes crashed into the Twin Towers and another into the Pentagon. Then, as the Towers fell, even more innocent lives were lost. That day is more emotional than one person dying, even thought that too is sad.
One day, 3000+ people die in the worst way imaginable.
9 years, 10,000+ die in the most typical ways.
I'm not saying that the deaths over nine years aren't sad, but those three thousand people were living lives to the fullest, and one day those lives are just plain GONE. It's probably the saddest day I've ever witnessed.
Sorry, your wording just sounded a little snobby.
Oh, sorry. I just realized. I can go change the wording a bit.