The recent spate of foiled terrorist plots by Muslim extremists in Great Britain, Germany and Denmark is a grim reminder that radical Islam continues to pose a serious threat in Europe. Some experts warn that Europe could export its brand of terrorism to the United States, since many of Europe's 15 million Muslims carry European passports that give them easy access to this country. European capitals like London have provided a haven for terrorists to organize, some critics say, because countries like Britain have failed to integrate Muslims into mainstream society. But other experts blame international terrorist networks, which recruit from a small minority of estranged European Muslims. Others argue that in fighting terrorism at home, countries like France have gone too far in curbing Muslims' civil liberties. Concerned that their secular Western values are under threat from conservative Muslims, some European countries are considering limiting immigration and requiring new citizens to adopt the national language and beliefs.

Sarah Glazer is a regular contributor to CQ Researcher and CQ Global Researcher. Her articles on publishing, health and social-policy have appeared in The New York Times, The Washington Post and Gender and Work, a book of essays. She graduated from the University of Chicago with a B.A. in American history