No doubt there will be time to reflect more deeply about the news announced by President Obama last night. For now, I thought it might be useful to annotate some of the initial headlines.

On where he was found:

Abbottabad is essentially a military-cantonment city in Pakistan, in the hills to the north of the capital of Islamabad, in an area where much of the land is controlled or owned by the Pakistani Army and retired Army officers. Although the city is technically in what used to be called the Northwest Frontier Province, it lies on the far eastern side of the province and is as close to Pakistani-held Kashmir as it is to the border city of Peshawar. The city is most notable for housing the Pakistan Military Academy, the Pakistani Army’s premier training college, equivalent to West Point. Looking at maps and satellite photos on the Web last night, I saw the wide expanse of the Academy not far from where the million-dollar, heavily secured mansion where bin Laden lived was constructed in 2005. The maps I looked at had sections of land nearby marked off as “restricted areas,” indicating that they were under military control. It stretches credulity to think that a mansion of that scale could have been built and occupied by bin Laden for six years without its coming to the attention of anyone in the Pakistani Army.

The initial circumstantial evidence suggests that the opposite is more likely—that bin Laden was effectively being housed under Pakistani state control. Pakistan will deny this, it seems safe to predict, and perhaps no convincing evidence will ever surface to prove the case. If I were a prosecutor at the United States Department of Justice, however, I would be tempted to call a grand jury. Who owned the land on which the house was constructed? How was the land acquired, and from whom? Who designed the house, which seems to have been purpose-built to secure bin Laden? Who was the general contractor? Who installed the security systems? Who worked there? Are there witnesses who will now testify as to who visited the house, how often, and for what purpose? These questions are not relevant only to the full realization of justice for the victims of September 11th. They are also relevant to the victims of terrorist attacks conducted or inspired by bin Laden while he lived in the house, and these include many Pakistanis, as well as Afghans, Indians, Jordanians, and Britons. They are rightly subjects of American criminal law.

Outside the Justice Department, other sections of the United States government will probably underplay any evidence of culpability by the Pakistani state or sections of the state, such as its intelligence service, I.S.I., in sheltering bin Laden. As ever, there are many other fish to fry in Islamabad and at the Army headquarters, in nearby Rawalpindi: an exit strategy from Afghanistan, which requires the greatest possible degree of coöperation from Pakistan that can be attained at a reasonable price; nuclear stability; and so on.

Pakistan’s military and intelligence service takes risks that others would not dare take because Pakistan’s generals believe that their nuclear deterrent keeps them safe from regime change of the sort under way in Libya, and because they have discovered over the years that the rest of the world sees them as too big to fail. Unfortunately, they probably are correct in their analysis; some countries, like some investment banks, do pose systemic risks so great that they are too big to fail, and Pakistan is currently the A.I.G. of nation-states. But that should not stop American prosecutors from following the law here as they would whenever any mass killer’s hideout is discovered.

Of course, Mullah Omar and Al Qaeda’s No. 2, Ayman al-Zawahiri, probably also enjoy refuge in Pakistan. The location of Mullah Omar, in particular, is believed by American officials to be well known to some Pakistani military and intelligence officers; Omar, too, they believe, is effectively under Pakistani state control. Perhaps the circumstantial evidence in the bin Laden case is misleading; only a transparent, thorough investigation by Pakistani authorities into how such a fugitive could have lived so long under the military’s nose without detection would establish otherwise. That sort of transparent investigation is unlikely to take place.

On who was living with Bin Laden:

The early reports suggest that he was living with his “youngest wife.” Bin Laden, who was fifty-three years old when he died, had always lived surrounded by family and children, so it is not surprising that he had managed to do so even as a fugitive. He is known to have married at least four times. His first wife was a cousin from Syria. His second and third wives were highly educated Saudi women. His fourth wife was a kind of mail-order teen-age bride from Yemen, whom he married while living in Afghanistan during the nineteen-nineties, according to the account of bin Laden’s former Yemeni bodyguard. Bin Laden’s Syrian and Saudi wives were said to have gone home before or immediately after the September 11th attacks, and the Saudi wives were said to be living in the kingdom, without contact with Osama. When I visited Yemen in 2007, to conduct research on the bin Laden family, Yemeni journalists told me that his youngest wife had returned home and was living in the region either of Tai’zz or of Ibb, significant cities to the south of Sanaa, the capital. It seems that she may have found her way to Pakistan to live with her husband. My own guess had been that bin Laden would have accepted informal divorce from his older wives on the ground of involuntary separation, and would have remarried a local woman or two while in hiding in Pakistan, perhaps a daughter presented by one of his Pathan hosts. That is at least conceivable as well. Apparently, one of his adult sons was killed in the raid. Osama has more than a dozen sons. Some have returned to Saudi Arabia, but others have appeared in videos with their father, vowing to fight alongside him. It is conceivable that one of his sons could make a claim on Al Qaeda leadership in the years ahead.

On what bin Laden’s death means for Al Qaeda:

On the constructive side: The loss of a symbolic, semi-charismatic leader whose own survival burnished his legend is significant. Also, Al Qaeda has never had a leadership succession test. Now it faces one. The organization was founded more than twenty years ago, in the summer of 1988, and at the initial sessions bin Laden was appointed amir and Ayman al-Zawahiri deputy amir. It is remarkable that, for all the No. 3s who have been killed, and for all the ways in which it has been degraded since September 11th, Al Qaeda had retained the same two leaders, continuously, for so long. Zawahiri is famously disputatious and tone-deaf. His relatively recent online “chat” taking questions about Al Qaeda’s violence did not go well. Bin Laden was a gentle and strong communicator, if somewhat incoherent in his thinking. Zawahiri is dogmatic and argumentative, and has a history of alienating colleagues.

On the other hand: Al Qaeda is more than just a centralized organization based in Pakistan. It is also a network of franchised or like-minded organizations, and an ideological movement in which followers sometimes act in isolation from leaders. The best guesstimates are that Al Qaeda has several hundred serious members or adherents in Pakistan, along the Pakistan side of the Pakistan-Afghanistan border, and perhaps up to a hundred scattered around Afghanistan. Just last week, the German government disrupted a cell near Dusseldorf in which one of the members, of Moroccan origin, had allegedly travelled to the Pakistan-Afghanistan border, where he received explosives training from an Al Qaeda contact. Al Qaeda in the Arabian Peninsula, based in Yemen, appears to be just as potent. Dan Benjamin, the State Department counterterrorism coördinator, gave a speech last week at New America that provided a very good, up-to-date summary of Al Qaeda and its affiliates worldwide, their capabilities and connections to one another.