What really worries me is that bin Laden could have paid for the Pakistanis to build something truly frightening: a thermonuclear bomb. Imagine a bomb with a yield in the 150-200 kT range--something like that detonated at Times Square in NYC will just about flatten every building on Manhattan, severely damage the western part of the Bronx, Queens and Brooklyn, and heavily damage cities on the New Jersey shoreline of the Hudson next to Manhattan. A death toll in the 1.5-2 million range is what will happen from such a device. (eek!)