I am reading some parts of Ahmed Rashid's Jihad: The rise of militant Islam in Central Asia, and I have just bumped into a description of the 2000 battle of Taloqan, featuring the Taliban's coalition against Massoud's alliance, on page 174, where Rashid gives the following breakdown of the former party's composition: 12,000 to 15,000 on the Taliban's side altogether*, 4,000 Pakistani militants (including people from the Sipah-e-Sahaba and the Lashkar-e-Jhangvi), 600 Arabs, 600 Uzbeks + miscellaneous + (support, Rashid alleges, from the Pakistan Army's Special Service Group).
Now, the trivial and yet surprisingly rarely considered thought which occurred to me is this: many of the same people, or people who have taken the "torch" over from them, so to say, but for some of the same organisations/movements, are fighting these days, too. For an Afghanistan without ISAF and the Karzai government - "Kashmiri" groups, al-Qaida, IMU, but also Haqqanis, Mansoors, Hizb-i-Islami/Hekmatyar etc.; for an Afghanistan where the Taliban's alliance can come back. That they joined the caravan is an investment by them in the future, and one they must have considered carefully, after all it is a matter of life and death.
Some helpful illustration about who is fighting where, indicating some of the active factions (plus I should add the caveat, just discussed in the comments, that given what has been reported on this blog as well, earlier on, some of this map, e.g. in the north, is just simply wrong; nevertheless it can at least convey a sense of the diversity within the ranks of the insurgency and that is why I am primarily using it in this post):
* Corrected; in the earlier version I wrote "of the Taliban's own."