Why are Obama and Holder so insistent on holding the 9/11 trials in civilian courts in NYC?

I helped out as a volunteer for two weeks after 9/11 at the WTC site. I was a witness to the destruction and harm done to NYC, particularly the areas around lower Manhattan. No one in NY, even the cowardly politicians who once gave the OK now want the trial in NY because of the pain and destruction it will add to the city. Why did Obama say again today that he might still hold it in lower Manhattan? Is he so blind to the obvious implications of that move?