Gary Becker and Richard Posner
have disected (or destroyed) the French Family Values column that Chris
mentioned. Posner’s analysis of the difference between the militance of
Muslims in Europe and in the US echoes the Economist‘s commentary on why the IRA disarmed. It comes down to welcoming people and providing them economic opportunity.

Affluence
heals many wounds. Why do young Palestinians blow up Israelis? Because
their economy is a shambles (while Israel’s thrives) and many of them
are still kept in refugee camps in Jordan rather than allowed to take
Jordanian jobs in another decrepit economy. As long as most of us in
America do not forget our immigrant heritage, we will also welcome new
immigrants, thus helping alleviate another source of tension. Can it be
that free and open societies inherently provide some measure of their
own security?