"...when the terrorists strike (whether they be from Al Qaeda or the IRA or the Hamas or Lashkar), they are part of a small group..."

If you are speaking of "card carrying" members then the groups may be small. If you start including those that support them, without being active participants, the group becomes much larger. Support can range from being the parent to those that provide food and shelter.

A perception in the USA is that many Mosques preach death to the infidels. Is that perception correct? I don't know, and maybe the number is small. My believe is that most Muslims are peaceful, but I understand how the excesses of the few causes problems for the masses.

The USA is a representative form of government. That does not mean that the representation reflects the will or thinking of the masses, or that the masses condone or support the views of the representatives. It is true that if you do not support the position of the CEO of your company you can quit. This November many of us will "quit" this representative body because it so often did not reflect our will. When I wrote my Senator and Representative about bailouts, and was ignored, I reserved the right to not vote for them.