Look, any large population shift brings tensions, drama, and the odd nutcase. It's bound to happen. At least 1% of every human population has a severely debilitating mental illness, and about 5% of most populations are mentally ill in some form. Add to that living in a conflict environment, seeing the atrocities they've seen, and living under tyrannic regimes, and sure, you're gonna get a few worriesome stragglers. So what? Western European countries are equipped to deal with it. The vast majority of these refugees have settled in Turkey, Jordan and the Lebanon anyway.