Parallel Societies

I'd seen this quote from the European Human Rights Court before, but it really struck me when I read it yesterday (here):

The (German) Federal Constitutional Court stressed the general interest of society to avoid the emergence of parallel societies based on separate philosophical convictions and the importance of integrating minorities into society.

It's a good point. If you're not careful, you'll have those Amish people breaking into comformist public schools and shooting the children.