When you do not allow people to assimilate then they retract, as they do so distrust evolves. By essentially tossing migrants into prison camps and not allowing opportunity you are showing that you are exactly like radical Islam tells them, now what do you think happens from there?

America worked only as a melting pot because there was opportunity, had that opportunity to advance and live not been there, she would have self destructed immediately. With the rise of extremist groups UN America she still might.

Your horrible migrant crisis is what America faces every year, in fact yours is watered down like crazy in comparison.
Now with migrant clampdowns happening as low IQ radical right wingers come unhinged we face economic problems as a result. As they arrest or deport our crops rot, as they rot Tax dollars are lost, as they leave local stores suffer as they lose customers.
Those that stay stick with their own as they do not feel safe, that is where gangs come from, in fact that is how radical groups are born. If I again look at the dark past of Germany we know how bad mustache man came to power under the same basic ideals. I would hope a history lesson on this regard is not needed.

One you have two choices, you can walk to that camp and show some humanity, or you can poke the dog with a stick and see how long it is until that dog bites back.

Btw the US rebuilt Europe and forgave your debt so you could prosper, it worked wonderfully, had we not the problems never would have ended.