Even in Iraq, most people go about their normal lives without worrying about dealing with terrorists. The suicide bombings are mostly in Bagdad, not in every city in the country. For most people in the United States, having to deal with terrorists, or even with ordinary criminals, is only a rare possibility; there is more of chance of being killed in motor vehicle accident than every even seeing a terrorist. However, no matter the slight chance of ever having to face a terrorist threat, when it happens to you, it has a 100% chance of occurring.
Intensely training for something that is only a remote possibility is a waste of resources. Even people whose job is responding to disasters do not spend a lot of time training for remote possibilities. In earthquake prone Oakland, California, fire departments train more for fighting the yearly grass fires than they do for earthquake response.
If one trains in the martial arts for the purpose of fighting to the death, the person will soon tire of the training and will probably stop any type of martial art training. If one trains in a martial art for fun, then the person will probably train for a lifetime. Which is better?