An Islamic Caliphate in NW Iraq/NE Syria?

I posted this original question 4 months ago. And here we are. ISIS has a stronger hold on the territory that it has claimed and are fighting to take more everyday. What large city in Iraq is next? Baghdad?

Not surprising, with their advances so far in Iraq they feel that they have the momentum to declare themselves to be an actual state. I feel personally that they are overreaching and with their pronouncements and actions that they will turn most of the legitimate nations of the Middle East against them. I also have been thinking the last couple of days about how long Israel will sit idly by while this is going on in their neighborhood, my personal feeling is that they will not sit by for long with this threat so close by.