Isis is a barbaric band of Muslim extremists who sought to go further than al Al Queda, drawing nearly all of its recruits into their suicidal warrior group. In their minds, they simply have to sacrifice one soldier to kill as many westerners as possible before they die. If they actually sat down to do the math, with the current numbers and birth rates, they would have to kill 100 to 120 people before dying themselves. The truth is, there arent that many people living in the Middleast as opposed to the West. Their strategy is flawed. Given the far right political climate, it is not inconceivable that the West will conduct a justifiable pogrom in the Middle East very soon if the far right has their way, if jihadis continue to appear unstoppable.
When the world is running low on oil, a sharp drop in human population, and no forces to defend Middle Eastern oil, would create the conditions for justifiable warfare against Jihadis. Word of advice, Jihadis had better drop their weapons and walk away from all of this, they may just bring about the demise of the entire Middle East.