How daft does one have to be to assume that terrorists need to smuggle themselves into Europe among the refugees? And how delusional do you have to be to assume they don't have easier and quicker ways into Europe? I mean, they were able to engineer such a precisely planned and timed attack in Paris after all. Surely they have some resources, don't you think?
Seriously, does anyone with a tiny bit of intelligence left really believe they mix with refugees and then do the stressy and grueling, monthlong journey across the Balkan?
It's very likely the terrorists have been here for months or even years or were born here. And that Syrian passport, which they found among the remains of one of the terrorists, was very likely fake or left there on purpose. The terrorist's goal, mind you, is to antagonize us against all muslims.
And with the less intelligent parts of our populations it already seems to work...