What gives this endgame a bizarre twist is that al-Qaeda’s submission has been overseen by the Taliban, the Islamist militant group that the United States fought in Afghanistan in a largely fruitless 20-year war. Having won power in Kabul, the Taliban has sheltered al-Qaeda but suppressed any foreign operations — and it has attacked ISIS-K as a mortal threat to its rule.

The U.S. intelligence community announced what amounted to an obituary for al-Qaeda in Afghanistan this month, details of which were provided to me by a National Security Council official. Because it coincided with the anniversary of the Sept. 11, 2001, attacks, some observers saw the release as politically motivated, and it received relatively little public attention. But it’s worth examining because, if accurate, it suggests a moment of closure in what was a consuming American drama.

Al-Qaeda “is at its historical nadir in Afghanistan and Pakistan, and its revival is unlikely,” said Christy Abizaid, the director of the National Counterterrorism Center in a Sept. 11 statement. She cited declassified intelligence that the group “has lost target access, leadership talent, group cohesion, rank-and-file commitment, and an accommodating local environment.” Its ability to threaten the United States from Afghanistan “is at its lowest point” since the group migrated there in 1998.

Al-Qaeda “has only a small number of members left in Afghanistan,” the intelligence summary continued. A senior intelligence official specified that the number of core al-Qaeda members in Afghanistan now is less than a dozen. A second senior administration official likened this handful of surviving Islamist militants to “a nursing home for AQ seniors.”

Other analysts are less upbeat. A United Nations report this spring put the number of core al-Qaeda members in Afghanistan at between 30 and 60, and the number of fighters in the country at 400. A group called Critical Threats warned on Sept. 11 that “al-Qaeda is rebuilding its transnational attack capability.”

But career U.S. intelligence professionals argue that these more pessimistic accounts are wrong. U.N. reporting “describes an [al-Qaeda] presence that does not align with the [diminished] threat they present,” one senior intelligence officer told me. “I haven’t seen any data to support the idea that there is any real resurgence,” said Michael Leiter, a former chief of the National Counterterrorism Center, in an interview.

The Taliban’s unlikely role as a counterterrorism partner is a matter of self-interest for the mullahs. Part of the bargain for the U.S. withdrawal from Kabul was that the Taliban would stop al-Qaeda from using Afghanistan as a platform for foreign operations. U.S. officials say they have generally lived up to that commitment.

Some members of the Taliban probably knew that al-Qaeda leader Ayman al-Zawahiri was hiding in Kabul, likely sheltered by members of the extremist Haqqani faction. The CIA learned of his presence, too, and he was killed by two U.S. Hellfire missiles while standing on a balcony in July 2022. The Taliban didn’t react.

Against the renegade ISIS-K, the Taliban has conducted a brutal but effective campaign. “The Taliban has intensified [counterterror] operations this year, which prompted some ISIS-K leaders to relocate to outside of Afghanistan,” notes the declassified intelligence findings, adding that “Taliban raids in Afghanistan have removed at least eight key ISIS-K leaders.”

The CIA shares counterterrorism information with the Taliban, the senior administration official said, but not targeting data or “actionable intelligence.” U.S. officials describe other Taliban policies, such as their harsh repression of women and girls, as “appalling.” But in containing terrorist groups that challenge the mullahs, an implicit alliance of convenience continues. “We’re lucky, our interest and the Taliban’s interest align,” said Leiter.

This is a story that ends not in comforting black-and-white certainties, but, rather, in the shades of gray of the intelligence world. It’s hardly a unique example. The CIA worked with the intelligence chief of the Palestine Liberation Organization for nearly a decade in the 1970s even though he was viewed by Israel as a terrorist. To defeat the Islamic State in Syria, the United States continues to ally with a Kurdish militia that Turkey regards as terrorist.

A useful caution about the Taliban comes from Marc Polymeropoulos, a former CIA case officer who served in Afghanistan. “This may work for a very short period of time when our narrow interests converge, but I would not bet the safety of the American people on a medieval Islamic fundamentalist group with an extraordinary amount of American blood on their hands.”

Afghanistan is one of those places that recalls the saying: It’s not over until it’s over — and even then, it’s not over. But when the U.S. intelligence community says al-Qaeda has reached a “nadir” there, it’s worth notice — and reflection on the tangled process that brought about its expiration.