Dan Darling points out something important: The similarities between the London and Sharm al-Shaikh bombings suggests that al-Qaeda may still be far more centralized than people think. From what I gather, Darling's big on Rohan Gunaratna's thesis that al-Qaeda still maintains a fairly robust vertical leadership structure, coordinating activities among a broad swath of associations, cells and "franchises" from on high. Bin Laden and Zawahiri, along with their various subordinates holed up in Iran and elsewhere, are still calling the shots to a large degree. You might say that al-Qaeda's structure isn't fundamentally different from that pre-9/11, except that there are fewer quality leaders, fewer training camps, and it's harder to coordinate stuff. Gunaratna's view—again, assuming I've recalled it correctly—sits in contrast to Jason Burke's more popular thesis that "al-Qaeda" itself isn't terribly important as an organization, and has mostly become a rallying point for a broader Islamic militant movement. The main threat, in other words, comes from a bunch of very loosely coordinated or uncoordinated terrorist cells often inspired by bin Laden but not necessarily acting on his orders.

Having re-read Burke's book recently, I should say that he does seem convincing when he argues that the structure of Islamic terrorism today may well resemble the structure of Islamic terrorism in the early 1990s, when bin Laden was as yet a relatively minor financier and skilled terrorists like Ramzi Yousef and Khalid Shaikh Mohammed operated somewhat as freelancers—albeit freelancers with access to training camps in Pakistan and Afghanistan and virtually unlimited funds pouring out of private mosques around the Gulf. If Burke's right, that's the lay of the land post-2001, though the freelancers and terrorist cells are much, much less adept and ambitious than Yousef or Shaikh Mohammed ever were. On the other hand, Burke does seem to go out of his way to deny any links between, say, Zarqawi and bin Laden—or between Basayev's band of Chechen salafists and bin Laden—when that hardly seems certain at all, given what we now know. It's a brilliant book, no doubt, but it does seem a bit tendentious.

Clearly I don't know enough to "weigh in" on this debate. Intuitively, though, it probably doesn't have to come down to one or the other. Gunaratna could be right in that bin Laden, Zawahiri, al-Adel, and other al-Qaeda higher-ups are still very much coordinating a far-flung terrorist organization with franchises in Iraq, Egypt, Pakistan, etc. (The leadership here is probably a very small "hardcore" element, of 200 or less, as per Marc Sageman.) So sure, maybe the London and Egypt bombings were done with the help and blessing of bin Laden himself, from his cavern resort or wherever. But Burke could also be right in that al-Qaeda has become a rallying point or inspiration for wholly unaffiliated cells and freelancers to carry out attacks on their own. And then there's Sageman's middle-way view, that "al-Qaeda's fragmentation since the invasion of Afghanistan has left it metastasizing into local operations seeking legitimacy under its banner."

On the other hand, Islamic militants were killing tourists in Egypt long before anyone in the West even knew bin Laden's name, so I guess we'll just have to wait and see where the trails actually lead. Also, read Marc Lynch's post on all of this.