Well then, maybe a policy decentralizing these "capital" activities in the New York area is a good idea. Then it wouldn't be such an attractive target, as you say.
Actually, I suspect that most of those activities would carry on elsewhere if New York were leveled by terrorists, tsunami, earthquake, whatever, and no one would miss Manhattan. The world is changing and geographic location is no longer critical to "capital" activities. Viva la Internet!
Bit of an overstatemt, don't you think?