This is a solid history of the relationship (and/or lack thereof) between Al Qaeda and the Taliban dating back to the anti-Soviet jihad period and on through 2011, when the book came out. I regret only just now getting to the book (though I did follow associated commentary by the authors at the time). At the time of writing, the international military coalition in Afghanistan was beginning to shift towards withdrawal from direct combat in Afghanistan, and portions of the international diplomatic community were beginning to seriously explore prospects for some form of negotiated political settlement with the Taliban that could bring an end to the conflict.
The term “affiliated with” does a lot of work in terrorism and counterterrorism analysis; its determination can quite literally amount to a death sentence. This book sets out to make the case that while the Taliban leadership was indeed “affiliated with” Al Qaeda in some forms, playing (at-times grudging) host prior to 2001, they are fundamentally a local movement whose aims have little to do with Osama bin Laden’s internationalist jihadi program and who should be considered independent of our broader counterterrorism campaign against Al Qaeda. The notion that the two groups were fundamentally intertwined formed a significant portion of the causus belli for the Afghanistan invasion, and for the ongoing counterinsurgency mission that followed from the mid-2000s, so making this separation would prove to be a key requirement for any form of political reconciliation.
Four years later, it seems to me that this argument has pretty definitively won out. With Bin Laden’s death, the shift of Al Qaeda’s operational center of gravity to Yemen and North Africa, and the rise of ISIS as a counter-claimant to the international mantle of jihad, policymaker attention has largely decamped from South and Central Asia for the Middle East, and left the question of what to do about the Taliban to the regional specialists, who for the most part now seem to accept it as a real local political force to be dealt with (though the question of whether or not its members can actually be accommodated in the Afghan political system remains under dispute). If we’re still insisting these days that the Taliban renounce Al Qaeda as one of our red lines for talks, I’ve missed it. The Talban, as the authors note, have also been quite deliberate about maintaining this localized focus and separation from Al Qaeda (while still avoiding directly denouncing it), at least since they reorganized to the point where they were able to start offering a political program of sorts.
Beyond the policy argument, the book offers a well-researched (I can only dream of some day matching this book for body-to-footnotes and references ratio) history of both the Taliban and Al Qaeda. Since the book is spanning approximately four decades and two complex organizations, there is some brevity involved, including in some places where I would’ve preferred greater elaboration or analysis of the primary sources and interviewees being cited. (The historical record gets notably less solid in the chapters from 2003 onwards.) On the other hand, many episodes that are often glossed over in other accounts get close scrutiny here. Through previous work in Kandahar, the authors have unique access to some of the Taliban “political” figures; although they reference a few Taliban factions who might be more inclined towards the Al Qaeda internationalist vision (primarily the late Mullah Dadullah, the Haqqanis, and unspecified members of the “new generation” of Taliban fighters emerging circa 2009-2011 — I would’ve liked more elaboration on the latter point, which does not seem to have come to pass in significant numbers in the years since), there is less to work with in terms of those group's motivations or interests. There is a lot of valuable details on the early history of the Taliban’s foundation and its pre-foundational origins in Soviet-era Kandahar, and some on the Taliban’s evolving insurgency structure (up to 2011, at least); the Al Qaeda portions are probably best read as supplementary to other dedicated histories to the organization.
The ultimate point here is that organizational and individual distinctions matter, and that even groups that may appear to be closely affiliated (either due to shared circumstance, ideological touchpoints, or a common enemy) will have their own distinct motivations, priorities, and strategies. Even if you don’t believe that such distinctions merited a different course of action in the wake of 9/11 — and such alternative history exercises are largely an exercise in speculative hindsight — it’s worth underscoring that choosing to view groups as an undifferentiated conglomerate will constrain your policy flexibility, with potentially serious consequences. Making those distinctions in real time is extremely challenging, and requires deep investments in fine-grained knowledge of the sort that this book offers. Should be part of any Afghanistan bookshelf.