@pztrn It's not the "EU migrants" or refugees that set off bombs. Many of the ISIS followers are born and raised in EU countries but _leave_ the EU to join their cause.
And even if it were the refugees, why aren't we seeing more chaos? With several hundreds of thousands of refugees and immigrants, everyday life goes on just as usual. We spend a little more money on housing newcomers but that'll pay off later.
Remember that most of the people coming now are pretty well educated and had enough money to pay for smuggling themselves out of the country. At least more educated than the average inhabitant that complains how "dey dook urrr jerrrbs".