Well, one problem is that it is difficult to separate “Pashtun” from “profoundly ignorant” as a demographic in Afghanistan. Not to say that all Pashtuns are ignorant, of course, but almost all of the ones fighting for the Taliban are. They can’t even read the Quran- they are illiterate, so they get told about the Quran by others. They believe every conspiracy theory and bit of Taliban propaganda that they hear. They are thus very easily manipulated, because they believe in that doctrine that non-Muslims are untrustworthy (and cannot be a witness in a trial, for instance). They believe that we are out to destroy Islam. I guess what I’m saying is that it isn’t really the Pashtuns per se who fight for the Taliban- rather, it is the ignorant who fight for the Taliban, and most Pashtuns fall into that category, and maybe the ones who actually know better then find it hard to act against their fellow tribesmen, etc. This also holds for Nuristanis, who as a group make Pashtuns look well-read.
I have a war story I like to tell-
“The Solution is Prosperity”, remember? So the U.S. had this policy of supporting development, and a popular project was installing micro-hydro plants in remote villages. During my 2007 deployment in Naray (now FOB Bostick) our FOB radio station sent a message to the elders of a remote village near there- I can’t remember the name so I’ll say Shahmasur- that they wanted to talk to them about a micro-hydro plant and discuss any other needs they had. So, over the span of a month or so we had two different groups of men, who were clearly too young to be elders, show up claiming to be the elders from Shahmasur. The first group didn’t even look Nuristani. But, whatever- we showed them around, talked about medical support, and had the development guys give them the spiel on microhydro, gave them a halal meal, and sent them on their way. After doing this twice, finally a group of older grey-bearded Nuristanis showed up claiming to be the REAL elders from Shahmasur. After giving them the dog-and-pony show as well, we asked what the deal was with the prior two groups. They said that the Taliban had told them that the offer of the micro-hydro plant was a trick, and that anyone who showed up to discuss it would be tortured to learn where their women and land and possessions were, then killed so we could go take all of it. So, they first sent a group of Gojers and a group of local troublemakers. If we killed them, no loss.
Follow-up story: So, this made me wonder “what is a Gojer?” I’d never heard of them. I asked our interpreter and he got visibly angry and said that the Gojers had come to Nuristan to steal the land, and that everybody hated them. Which I guess would explain why they sent them first, but, really, “they came to steal the land”? So I googled when I got the chance and found out that the Gojers are descended from a tribe from India that had invaded Afghanistan in the 1200s or something, and the Nuristanis have been nursing that grudge for 800 years or so.
Oh, and another favorite, though it’s from Iraq not Afghanistan: The British got accused of releasing man-eating badgers in Basra to sow panic. Seriously. Most of Iraq still believes it, despite the predictable UK military response: “"We can categorically state that we have not released man-eating badgers into the area.” There is a strong tradition of believing conspiracy theories throughout the Muslim world, not just in Afghanistan.
But, to get back on track, most of the more ignorant anti-coalition Afghans do believe the propaganda that we came to rape their women, steal their stuff, and take their land. Which is all laughable, of course. 1) I don't want to sound bigoted or condescending or anything, but, I wouldn’t touch the average Pashtun woman on a dare- they tend towards unshaved and malodorous in ways that profoundly conflict with western ideals of femininity. I know- rape isn't about attractiveness. But I'm not a rapist. 2) What that they have could I possibly want? They are too poor to have garbage. Seriously, they are so poor that everything gets used- they line their houses with used cardboard as insulation, for instance. 3) If I owned Hell and Afghanistan, I’d live in Hell and rent out Afghanistan.
So, maybe that does constitute a perception of “invasion.” I dunno- that culture is so alien to me that I hesitate to make assumptions. My impressions could very well be sampling bias, too. Every Pashtun I’ve spoken with seemed rational, but heck if they thought I might set them on fire and rape their mother they might have been feeding me platitudes. FWIW the Dari-speakers as a general rule are better educated, and also tend to support the coalition. Just about everyone but the Pashtuns and Nurstanis support us, as a rule. When we tell THEM that we really just want to squash the Taliban, maybe help increase security a bit, and then LEAVE SKID MARKS on our way out of the country… they get scared. That’s basically everyone who doesn’t live near the Pakistani border (and even a lot who do). My interpreter during my 2011 deployment is a great example- he's from a town that is an island of Dari speakers in a Pashtun sea. Great guy- I sent him a care package of diapers and other trifles for when his wife delivered this summer. If he ever needs a reference to immigrate I'll send him one.
Anyway, even WITH the conflict going on now, he says things are better than they were under the Taliban. He is one of several Afghan who I have heard wishing for the U.S. to stay as long as possible.
So, really, I think it’s MOSTLY about poverty, though their ignorance and belief in the Taliban propaganda potentiates this. As I said, most of those fighting the coalition are desperately poor and are paid to do so, even the ignorant masses who buy into the propaganda. Oh, and to boot they are promised that their families will get even more money if they are killed. Estimates of the number of actual Taliban cadre in the country have never been above the low-hundreds since the initial invasion. The rest are paid fighters or belong to groups only tenuously allied with the Taliban, such as the Haqqani Network. Most of those are just warlords or gang leaders who use the “eject the crusaders” thing to get funds and weapons from the Taliban. We don’t even call these groups Taliban- we call them ACM (Anti-Coalition Militia). Heck, they regularly have fallings-out with the Taliban and proceed to kill one another for a while. (Which is always amusing- their assassination techniques deserve a certain morbid appreciation.)
Rage at perceived civilian casualties? Well, IMO like a lot of rage in the Muslim world I think it's really just a baseline rage, not really rage ABOUT anything. The stifling society of the Muslim world produces a LOT of Angry Young Men, who basically take any excuse to misbehave a bit, up to and including things like lynching those UN workers in RC-North when those bigoted morons at Westboro Baptist were acting up. The Muslim perception of "humiliation"- which is VERY important to them- at being bullied by the western world also contributes. (As does, I am quite certain, simple sexual frustration.) So, similarly, every report of civilian casualties is used as an excuse to hit the streets and blow off steam. Do you think a Hazara goatherd CARES if a Pashtun woman gets blown to bits in a strike on a convoy? Hell no! OTOH, of course, if your cousin or brother get killed that very well might radicalize one. In fact, it starts an immediate blood-feud. (One of the reasons that the U.S. goes to such lengths to avoid such casualties, and to make right in whatever way they can when they do occur.) So, yes, I'm certain that at various points someone has shot at Americans in retaliation, but most of them probably considered themselves as seeking revenge for a killing, not a jihadi. Hell, we've captured people who have flat out told us that they were avenging the death of a relative, sometimes even avenging the deaths of a relative who were killed attacking Americans in the first place. But Badal is a way of life there. Literally- it's a tenet of Pashtunwali.
Nonetheless, I don't think I can answer intelligently if the perception of massive civilian casualties pushes more Pashtuns toward accepting the AK-47 and $300. I think it's more of a source of anger that is unleashed in the Afghan media and political arena than anything else, and the Taliban absolutely play on that, but the culture is so alien to me that I wouldn't trust my impressions very far. I've also had Afghans tell me stuff like "they were stupid- they should know better than to be near there" regarding some incidents of civilian casualties. Eh. Wish I could be more helpful.