Meanwhile, our enemy in Afghanistan, the Taliban, was fighting motivated by their Collective Identity as Muslims. That motivation appeared to allow them to pull patriots from the population. That Collective Identity and the values associated with it was clearly a motivating factor among the insurgents. Once we realized the power of Collective Identity as a motivating factor in the target population should we have adjusted our COIN strategy? A similar question can be asked about legitimacy. If, in the target population, our efforts are seen as illegitimate, can we ever win?
I wonder about this. It is said that war is the continuation of politics by other means. It's also said that all politics are local. I have to wonder how many of those who fought - the actual fighters, not the leaders - were motivated by "collective identity" and how many were motivated by grievances or issues specific to their locality.

I do not think there's much point in trying to compromise with or reach accommodation with the leaders of these movements: they are too ideological and too deeply invested in goals that can only be achieved through violence. It may, however, be possible in some cases to disaggregate leaders from followers by addressing and resolving the concrete local issues that drive individual fighters to fight. I may be excessively attached to this idea because I've seen it work, and I certainly don't think it automatically applies everywhere. It's certainly worthy of consideration, though. I don't think we should ever assume that the motivations of the individuals carrying the rifles are the same as those of the leaders, or that a single set of motivations applies across any given movement.

It's certainly worth asking whether we can ever "win" in a place where our presence and efforts are seen by the populace as inherently illegitimate. Since "winning" is achieving one's objectives, we might be well advised to assess our objectives more carefully, and to determine before we start whether those objectives are compatible with local perceptions of legitimacy. The idea that a bit of "winning hearts and minds" can persuade a populace to accept and embrace the presence and agendas of an occupying army was always a bit optimistic.