I think the bar &#x27;economy deteriorated&#x27; is a high one. The issue rather is failure of migrants to integrate (probably fault of both host nation &amp; migrants themselves) - thus creating ghettos &#x2F; high crime rate &#x2F; risk of terrorism.<p>This is what seems to be happening - for example in France (banlieues, 70% of prison population is muslim, Charlie Hebbo).