"If al-Qaida terrorists are stuffing PETN into underwear or packages, that must mean that they do not have access to cutting-edge biological research or nuclear bomb components. On the contrary, they remain strangely fixated on airplanes and far behind the technological times. Clearly, this latest incarnation of al-Qaida is not benign: Islamic fundamentalist terrorism remains a threat. ... Yet although they are dangerous, although they are ruthless, these package bombs prove that al-Qaida, at least in its desert hideouts on the Arabian peninsula, does not pose a serious, existential security challenge to the United States."