How dangerous are the Taliban?

Foreign Affairs is having a discussion on whether the Taliban and al-Qaida are dangerous enough for keeping on fighting in AfPak. It is Professor John Mueller that asks the question.

I have earlier suggested that all effort should be directed to the Iraq situation and that AfPak could be counted on maturing on its own. My question is therefore if John Muellers view is the beginning of a policy change on the issue or whether it is his rather a lonely idea?