Mate , as far as i see our Pakistani friends tends make arguments from their experience with Taliban.
Nobody can be %100 sure about this issue. I'm just stating my opinion.
Iraq has a very weak army when compared to Turkey.
Also, Maliki's secterian policies helped ISIS to gain support from the sunni population. There is no base support for ISIS in Turkey.
At most they can explode bombs in border gates, some ISIS guys can infiltrate and can blow them selves in crowded places, they can target our patrolling vehicles on the border. They can never control a region or land in Turkey.
Turkey's response can be very harsh and they will be inflicted more damage then they inflicted.
Mate, regarding PKK...things are call since 2013. Also they are 5000 manned terrorist organization with hit and run-tactics..Yeah, they were disturbing us like a mosquito but they can never militarily challenge Turkey.