Question: How would ISIS cross the "air gap" between their conquests in Iraq and Saudi Arabia?
Answer: It already has.
ISIS has become the leading supplier of the most potent drug in the world:
More than half of Saudi Arabia's men are under 21 and most of those boys have been given a religious education in a strict literalist tradition. Further, they've been kept in time capsule, protected from many of the changes influences the rest of us.
To young men like this, ISIS is pure historical heroin. It's a jihad in the medieval tradition (made successful by using the techniques of open source insurgency).
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