Lots of morons think this is a good idea because hurrrrrrrrrrrr fewer refugees. Thing is, those zones are not needed. There is plenty of room in the surrounding countries for any refugees, and if you want to be really safe, just go to Syrian government-held territory. There are lots of Syrian government-controlled areas that are very safe.
This whole thing is a scam by the Saudis to occupy Syrian land and protect their jihadi pals like ISIS and Al Qaeda. By doing this, we are supporting ISIS, Al Qaeda and all the rest, but we have been supporting them since Day One anyway.