I suspect Zawahiri began such planning in complete secrecy about three years ago; he announced his intention to launch another mass casualty attack in the US in his 2008 book, “Exoneration.” Now that he has taken over the reins of Al Qaeda, Zawahiri needs to establish himself as a force more than ever.
If he’s following through, the people directly involved in planning the next big attack may have been cut off long ago from vulnerable, main lines of communication. The Al Qaeda core knows that a dedicated focus and compartmentalization of an operation is the only way, in today’s hostile counterterrorism environment, to ensure the survivability of a plot.
There are not many operatives of Adl’s and Shukrijumah’s caliber in the hollowed-out Al Qaeda core, but there are enough of them to plan and carry out the next large-scale attack.
One who meets these qualifications: Abdel Aziz al-Masri, the man who led a secret project to conduct nuclear bomb-related tests in the Afghan desert in 1998. Al Qaeda’s nuclear CEO was last reported to be in Iran with Adl in mid-2003, when the group was shopping for nuclear devices, technologies, and materials.
In addition, a Pakistan nuclear specialist apparently recruited by Al Qaeda has not been identified, and is presumably at large. Recent media reports indicate a senior Al Qaeda cadre under house arrest in Iran has been allowed to leave the country, suggesting some key weapons- operatives may now be free to engage in operational planning.