Of course this makes the assumption that the areas considered "problematic" will remain static. I would disagree in that the problem seeks the base as opposed to staying in one location and dying off like a species of tree or shrub that only lives in that environment.
Islam has repeatedly become problematic for Europe through the centuries. The difference now being that the conditions in the host nation are no longer the only thing that control the increase or decrease in the available group. Pakistan may come out of its 'Bulge" but the base has simply relocated to areas that present an environment where the numbers available can grow (UK, US...other western nations) due to much better moratlity rates.
I would also argue that there doesn't necessarily need to be a large youth population....
Parallel the decline in younger numbers in the "problem" areas with a similar decline in the nations that are working to counter the terrorist base.
[Given the current world financial issues, I am cautious to take on the ideas of someone (formerly) from Citigroup]
Just my thoughts...
http://www.khouse.org/6640_media_ser...w_day=thursday