Rebuilding WTC Towers: Economic And Security Challenges

"Many fear that whatever replaces the old center would become a new target for terrorists...But others noted that the 10.6-million-square-foot center represented one-tenth of the total office space in lower Manhattan. As much as 20 million square feet of space reportedly is sitting empty in Manhattan, but even before the World Trade Center collapsed, big blocks of contiguous space were rare...Beyond the practical concerns, talk of rebuilding also may run headlong into a desire to turn the area into a memorial to the victims."