The smoke over Manhattan did not reach the dimensions of a mushroom cloud, but the number of casualties was close to that of a small nuclear explosion. The scenario of nuclear weapons in the hands of terrorists is a nightmare that has been discussed from time to time but had been considered unlikely. It was believed that they still had an interest in creating sympathy for their cause and avoiding a high death toll. After September 11, this view must be questioned.
These terrorists aimed at as many deaths as possible; future assassins might develop the perverse ambition to top even that number. Weapons of mass destruction, especially nuclear weapons, would be the next step in escalation. In a 1998 interview, Osama Bin Laden admitted that he would not exclude their use and that he perceived it as his ‘religious duty’, to use them.