TCNY, you asked for references -- for which assertions?
LtEve the reason why I thought your comment might be aimed at me is because one of your previous comments was, I responded directly to you, and you then posted on a related topic. So it was less about ego and more about a not-exactly-surprising logical chain. Hey ho, it gave you the chance for another ad hominem attack. You say that being involved in the war gives members of the armed forces and those who know them well a materially better understanding of Afghanistan. I think the very personal involvement makes it very difficult to maintain sufficient distance to conduct dispassionate analysis. It's not a lack of detailed facts about specific deployments eg whether to have a FOB here or there -- that's at issue: it's whether the whole effort is beneficial or not, to us and to the Afghans. That requires a net calculation: no point in just counting the positives or just the negatives. So talking about defusing IEDs, as others have done, rather misses the point that the IEDs were only planted because we were there. Talking about the abuse of women under the Taleban in pre-invasion days must be weighed up against the fact that many Afghan women still live under Taleban rule, many others live under harsh and bigoted non-Taleban rule, and the Afghan government itself has instituted all sorts of misogyny of its own: there's probably a net benefit, but it's not enormous and other approaches, especially direct economic support for women through eg microloans, seem perfectly plausible alternatives and don't have the advantage of having to kill everyone.
You asked "how could I know that not one of the reasons for going to war in Afghanistan is valid, if I don't know all the reasons"? Because not one of them could conceivably involve an existential threat to the UK, and that's the only reason that's valid. As I said earlier, the Afghan war has destabilised Pakistan, which is really bad news as that state could conceivably pose an existential threat to us, given the volatile mix of Islamists and nuclear weapons.
Ididthisforus: "One recurring theme seems to be that we are more at risk because our Forces are, for want of a better phrase, occupying, another country. Are the holders of this belief really that naive to think that the Taliban, or any fundamentalist terrorist organisation for that matter, would not class Britain as a target if we weren't in Afghanistan? On the contrary, we are a target by virtue of the fact that this country does not live by their fundamentalist beliefs, as is any other democratic society with the freedom of choice."
This is arguing with a strawman. I don't know of anyone who thinks we wouldn't anyway be a target if we hadn't invaded Iraq and Afghanistan. However, lots of us think the invasions were counterproductive because we're more of a target: there's lots more angry people out there with a grudge against us. Additionally, what I believe is that it is a scandalous waste of resources to deploy military forces to combat terrorism. It's the wrong tool for the job. Armed forces are to deal with existential threats, which terrorism is not. Terrorism can be better tackled through other means, as I posted upthread.
LeQueen -- weird comment re Wilfred Owen, possibly the most famous British poet of all time to express doubts about the wisdom of war. Even weirder comment about spelling: Taliban / Taleban are English transliterations of an Arabic word. There is no standardised transliteration of Arabic words in English: Mecca and Makkah are both valid, for example. Your assuming of the intellectual high-ground on this point has just left your arse hanging out, frankly.