I'd guess Kill, and not capture, orders are the norm for these guys now.....I'd bet there is a simple extermination process taking place now.Why should you follow the rules of war if your enemy does not.
ISIS and the other Islamic terrorists organizations are not like ordinary States. Killing the top guy will only get his deputy promoted. And there are hundreds and thousands lining up behind them waiting to be promoted or to become martyrs.
The West, and the US especially, never got over WW2: taking the leader out (like Hitler) would get the war to come to a screeching halt. They still think that a key drone strike against the 'Leader' will do the same. Not so with Islamist ideology. Many are only too glad to get blown up so they can go to heaven with accompanying perks.T
he Syrian Army has been wasting these terrorists for 4 years now, and there is no shortage of martyrs to replace them. So wanting to assassinate their leaders is not going to do anything because it's not the individual leader that needs to be taken out, but the ideology.
This is a dare to Jordan. If Jordan wants to seek effective revenge, it will have to engage in a full scale invasion of ISIS territories. But that is a risk for a conventional army, as it will become mired into fighting insurgency, and that is what ISIS is counting on. I doubt the Jordanian Army, the most competent and professional Arab army (but no battle experience since 1973), will undertake this venture. There is already a coalition to fight ISIS. But there are no boots on the ground, except in Iraq with the Iraqi army (incompetently) defending its homeland. There is also Syria with the help of Hezbollah, but they have not been allowed in this coalition, despite the fact that they have done the most damage and most of the fighting against ISIS.