1) The Western forces seem to be emphasizing attrition over intelligence. IOW, still fighting the last war. Throwing money (weapons, supplies, etc) and personnel at the problem, relying on the deep pockets of the American taxpayer, etc.
2) The Western forces seem to be more focused on proving they're right and capitalizing on the victim status than winning the war. IOW, the West seems unwilling to dismiss convention for the sake of success.
3) The terrorists seem to be have made a huge impact with minimal resources. Their propaganda campaign seems much more effective, as there seems to be no shortage of recruits. Even moderate Muslims who disagree with their tactics and philosophy are sitting on their hands, probably out of fear. The US, however, is having to bend every rule it can to keep up its numbers. Extending tours of duty, recalling active vets, etc.
4) The terrorists seem to know more about us than we know about them. They have our psychology; we don't have theirs. Shades of Vietnam?
I admit that I'm very ignorant on what's happening behind the curtains on both sides, but it seems that the guerrilla tactics applied by Al Qaeda, et al, mesh more closely with what Sun Tzu taught than those of the West. What am I not seeing in this picture?

The dramatized, hyped version for those who don't want to read through all the archaic language in the link above:
[youtube]http://www.youtube.com/watch?v=Oe1rfMpB ... re=related[/youtube]
[youtube]http://www.youtube.com/watch?v=HeBohmXp ... re=related[/youtube]
[youtube]http://www.youtube.com/watch?v=Aj5WxDdQ ... re=related[/youtube]
etc, etc. You can find the rest at Youtube, if you're interested.