It is unlikely these terrorists were refugees. The refugee wave just happened. These people were organized. However, it is irrelevant. If a country wants to refuse refugees for any reason or no reason, it is that country's right. In this case, there is a really good reason: Muslims keep killing people in host countries. But it is OK - keep your head in the sand, this can keep happening, and you can keep making shrill red herring arguments when people keep pointing out the obvious solution.