It has long been known that a religious maniac with a sharp sword is the worst of all enemies, and that is what we are faced with here. Any appeal to their humanity is vain; they might negotiate over an offer of an immense ransom, but we have rightly set our face against this, for: "if you pay anyone Danegeld, you never get rid of the Dane" (Kipling) - your nationals become the hostages of choice. The only hope is: he is more valuable to them alive than dead.
So it's a case of God (of your particular belief) help him, for no human power can do so now.
I would think our Intelligence is working overtime to discover what kind of weapon (if it was a weapon) was used, for if it can claw down a Jordanian modern ground attack aircraft, a Tornado (a 40+ year old design) might be next.
We were supremely confident in the invulnerability of the U-2 until one day over Smolensk....
D.