Daniel Pipes has an item on the rioting in Holland, which, while less serious than the WTC and Madrid, involved more Muslims.
Enough to make it a full-on civil war type situation, kind of like the Watts Riot. He writes:
There have been larger Islamist attacks in the West – such as the two assaults on New York`s World Trade Center and the Madrid train station bombings – but nothing has resembled the civil-war quality of the 15-hour standoff in The Hague, Holland, yesterday. [Weblog A Muslim Uprising in Holland? November 11, 2004]
This can happen here, you know. It might not be Muslims, who aren`t concentrated enough, most places, in the United States, the way they are in Europe.
The point is that if you import millions of people from riot-prone areas, and cluster them in barrios, banlieues, or whatever, then rioting is more or less to be expected—unless the Administration starts enforcing the immigration laws.