Afghan will be the next caliphate country
ISIS might try and claim that, but if you read their history over the last couple hundred years, NOBODY outside Afghan is really ever gonna run that place.
You might enjoy this: http://books.google.com/books/about/The_Man_Who_Would_Be_King.html?id=R2Q51iIenvEC
It won't even take a battle, and no other country will be willing to fight there again. Question....what's to keep the Caliphate from spreading into Pakistan?