I think the big question should be, why, out of the large number of countries that have suffered because of instigators and financiers like this, none of them have started a program of assassination against them.
Seriously, some guy like this Saudi pig poop should have been reduced to a grease spot a decade or more ago. Make it look like an accident, if you want, but put an end to them.
If possible, even make it look like it was done by the same fanatics they were supporting.
Take a look here concerning the OIC: