It was a guy on a bicycle who tossed a low-powered homemade bomb, little more than a firecracker.
A Muslim terrorist would blow the place to smithereens in the middle of the day when there were people in it.
Good analysis.
It was considerably more than a firecracker, and letters were sent by the perps.
http://hotair.com/archives/2008/03/06/surveillance-video-the-times-square-bombing/