International counterterrorism is said to have been successful in "degrading Al Qaeda as an organization and in decreasing its ability to conduct massive attacks." What survives is "a patchwork of homegrown networks and 'lone wolves,' where almost everyone can be linked, at least indirectly, to almost everyone else," but in casual and nonoperational ways.
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European security agencies have reported "a growing tendency of self-radicalization and self-recruitment." The latter is now thought to be more important in producing jihad candidates "than any organized international network,"
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This radicalization of young Muslim militants in Europe is superficially religious, but usually takes place outside mosques and "more often than not involves individuals with college education."

The sources of extremism are social and political alienation, exclusion (and unemployment) among the offspring of immigrant communities, but the international drama mobilizes them.