I think pakistan is already the new afghanistan. Bangladesh is actually a democracy, and has been for some time. I'm very skeptical of the idea that democracy is the best impediment to islamism.
BanglaDesh is relatively messed up but does a have a functioning democracy. There hae been rumours and allegations of terrorists being there. I believe it is either number one or two on the Most Corrupted countries list.
I know some Bengalis and they seem alright apart from the reigious mania. As the country floods so regularly to about 40/50% of the land, its use as a hide out may be questionable.