Just to clarify a bit on this previous post, the only national security interest in preventing a Taliban victory in Afghanistan is based on the premise that if they could return things to the status quo ante, they would continue to maintain a relationship with al-Qaida. I happen to agree that this is likely if they could “win” to that degree. But I’m not sure they could actually do that, especially if we maintain support to the Afghan National Army.
It could also be that the al-Qaida leadership feels safer where they are now, or elsewhere, or a decentralized combination of the three (Afghanistan + FATA + elsewhere). Joshua Foust maintains that “The 1990s cannot be written off as a one-time thing. Many of the ground conditions remain the same.” But neither can a return to the pre-war situation be assumed as a given.
One mistake I think critics make, though, when it comes to the importance of preventing safe havens is that they tend to focus on planning, pointing out that the 9/11 attacks were planned in Hamburg, and that modern communications make centralized planning obsolete. But safe havens also allow for training camps and recruitment channels for militants who can then go on to destabilize Central Asia, or return for attacks in Western Europe, for instance. So preventing them is a national security interest of strategic, if not existential, importance.
But again, it’s not certain that Afghanistan will ever again be as attractive a safe haven as it was pre-war. And keeping it from becoming so is a strategic burden that Pakistan, India, Uzbekistan, Russia, China and the EU have an interest in shouldering, too. I think it’s more likely they will do so if we draw down.