Not unless they change their constitution.
Besides, it would be moronic if they did.
Go to war because a bunch of lunatics killed two of their countrymen who should have known better then to be there?
These two idiots partially brought it on themselves by being non-Muslims and voluntarily going to that part of the world at this time. You go there right now (assuming you are western/east Asian) you are just asking to be killed by some lunatic terrorist.
If you deliberately put your head in the lions mouth, it is at least partially your fault if it bites it off.