We can keep PKK at bay and crush them like we're doing now. On the other hand, 20mil+ aliens(if no precaution is taken) will extinguish the very fabric of the society that makes up Turkish identity. You cannot expel them with soft power once they're over ten percent of your population. And God knows how bloody it will be once they're over the inflection point.NOTHING is more important than PKK when you consider what U.S. doing in Syria today , how much TAF lost its edge thanks to sanctions and more importantly the fact we are living together 8 million + strong fifth collumn.
I reiterate, the refugee problem will become BIGGER than PKK if we're oblivious to this threat and not take the necessary precautions.