Terrorism and Immigration Policy--Posner's Response to Comments
There were many good comments. The common thread in many of them was that an economic analysis leaves out equally or more important "cultural" or "sociological" factors that cannot be reduced to economics. I do not deny the possibility that factors about which economics may, at least at its present level of development, have little to say may be extremely important in explaining the phenomenon of terrorism, and specifically why sympathy for Islamist terrorism appears to be more widespread in Western Europe than in the United States. One is simply the fact that because of our proximity to Mexico, most low-wage immigrants come from there rather than from the Islamic world. Another is that, as a nation of immigrants, the United States provides a more welcoming environment for immigrants; the Western European countries, in contrast, were, until recently, mainly nations of emigrants, and they may simply not have learned yet how to assimilate large immigrant populations. In addition, as Becker mentions, the fact that the United Kingdom has a serious problem of Islamic extremism doesn't sort well with the fact that it has relatively open labor markets and a porous safety net, much like the United States. One factor retarding assimilation of immigrants in the United Kingdom may be the class system.
But I believe that economic factors are important contributors to Europe's Muslim problem, and being underemphasized deserve special consideration. When mentioned they are usually related to poverty, it being assumed that poverty foments terrorism. But as I said in my original posting, the evidence for this is weak. What is important is the effect of economic institutions on the self-selection of immigrants and on their incentives when they arrive. If economic institutions such as open labor markets and a low safety net encourage the immigration of strivers, they and their children are unlikely to feel like resentful outsiders.
The materialism of America's capitalist culture came in for some knocks from some of the commenters. But as Samuel Johnson said, people are rarely as innocently engaged as when trying to make money. Commercial values historically and today are inimical to the pursuit of Utopian fantasies and the glorification of violence.
Several comments misunderstood me to be arguing that long vacations cause terrorism. That of course would be absurd. My point was that a system of regulations that discourage work create a barrier to the integration of immigrants. As one commenter pointed out, Paul Krugman's statement that productivity is higher in France than in the United States mistakes a problem for a solution. A nation that makes it difficult for low-skilled workers, who therefore are not highly productive, to find jobs will have a high measured productivity, but that productivity advantage is an artifact of failing to make full use of the nation's productive labor resources.
Several comments expressed in the manner of Krugman a preference for the French way of life, with its greater emphasis on leisure. But this preference fails to reckon with the profound costs in economic stagnation and diminished fertility, which in combination with public policies that discourage work have forced Europe to import huge numbers of Muslim workers without being able to assimilate them. The problem will not be solved by celebrating the joys of leisure. The policies that encourage leisure have contributed to Europe's serious, perhaps critical, problems. To these problems Paul Krugman seems oblivious.