They have great aspirations of grandeur to take over the whole world and enforce their Sharia law. I don't see how most Americans could possibly adjust to that way of life.
Luckily, we wont stand for that sort of non-sense here. They may hit us with terrorist attacks and behead American's over there, but they have no way to get here, no way to invade, and no way to beat our military on our soil.
And even if they or some other foreign force did make it to America and defeat our military, no invading force could match the 75 MILLION plus gun owners in America who would rise up and create the largest, deadliest insurgency in the history of warfare. Put plainly, invading America would be a guaranteed suicide mission for all invading forces. I don't think that if all the worlds armies combined invaded America at the same time, that America would lose. Invading forces would suffer so many losses through attrition that they would eventually give up and go home.
"You cannot invade the mainland United States. There would be a rifle behind each blade of grass." - Admiral Isoroku Yamamoto, Japanese WW2 leader