Gburg the islamic threat in Nam is real but very low key. The commies have kept the local ones very well in check. Sporadic "niusance value" attacks (which the commies will make sure you never read about) have only been aimed at the government. And if I recall correctley about 6 local islamics were executed about 8 months ago when they tried unsuccessfuly to blow up a government staff canteen (in Da Nang I think).
I believe any real trouble in Nam will originate from imported islamics and not the local ones. The locals know theyll be shot without question if they try anything.