I'm gonna be blunt. I'll take the heat for making this statement.
I don't have any problems at all with executions of known isis jihadis.
"Mass" or otherwise.
As far as The West is concerned, when a muslim joins isis, he is signing his own "death sentence".
To join isis means that he has willingly discarded the bounds of the civilized world, to join a group of savages and animals. Rabid dogs deserve better treatment.