You're seeing a portend in Iran and maybe Iraq. Folks get democracy. They vote in Islamic law. Impose Sharia. THAT would be fun, eh?
Now, look at the growing young Muslim populations in France, Belgium, Holland etc. at a time when the Euros are not replacing themselves at 2.0 kids per couple. These immigrants as you well know from recent news reports are NOT assimilating into the adopted cultures. In a couple decades, expect to see Islamic Law on the ballot.
An idea. One way to forestall the inevitable might be to ammend constitutions NOW such that over 2/3rds of the population is required to vote in any type of a "religious" law, whatever that legal definition might be.