The trouble is that governments frequently lump in criminal actions with regressive norms. Germany is leading a drive to curb foreign influence of mosques, train imams and control funding. France wants to cajole Muslims into a representative body. They are echoing the Muslim world, where Islam is often a state religion that is run, and stifled, by governments.
However, the top-down nannying of religion risks a backlash. Heavy-handed interference will alienate communities whose co-operation is needed to identify potential terrorists and abusers among them. Put on the defensive, Muslims will deepen communal identities and retreat into the very segregation that intervention is supposed to reverse.
Rather than intervene in doctrine, it is better to deal with social conservatism through argument and persuasion. That can make for testy debate. This week Ilhan Omar, a Democratic congresswoman from Minnesota, had to apologise for peddling anti-Semitic tropes. The trickiest balance is over how to counter the radicalisation of Muslims, whether online or in prisons. This often involves vulnerable young people becoming more devout before turning to violence. But there are signs of progress. Although young Muslims are conservative by the standards of Western society (eg, on gay schoolteachers), they are more liberal than their elders.
Islam belongs to Western history and culture. Muslims have governed parts of Europe for 13 centuries; they helped kindle the Renaissance. If today’s varied and liberal form of Islam continues to flourish, it may even serve as an example of tolerance for the rest of the Muslim world.