I agree with the previous two posters. Having post-service had a little career concerning middle east problems I can say that ISIS are definitely different from all others. The present ISIS operation is practically a re-write of the 1802 revolution in which the Wahabis took over Saudi Arabia. Saudi is the home of Sunni Wahabism and has spawned both Al Quaeda and ISIS. But ISIS are really sticking to the original play of 1802. Their objective is a Caliphate - a religious state led by a successor to mahommed - and they have openly stated that they want that to include Europe.
They will fight for years and since they virtually never field an army, they are difficult for the conventionally armed westerners to deal with.
These people are deadly serious and they have gone out of their way to try to scare us into submission - and as far as the politically correct, atheistic liberal left is concerned, they seem to have done a pretty good job.
ISIS - as has been said will never get into negotiations - that is of no interest to them. They want territory and they want to dominate the moslem world with us included in it.
We should in my view be supporting Al Assad in Syria. He is an Alawite - regarded by both Sunni and Shia as non-moslem. He works well with the Christian population (and there was a large Christian population in Iraq, Syria, Lebanon, Israel and Palestine) He is in fact western culture-friendly. He understands what should be done there. Building on him and his army and the Iraqi army together with the Kurds, we might just be able to surround and defeat ISIS.