Iran has a legal right to strike Saudi Arabia
One of the reasons that Qatar is so easy to single out as a state sponsor of terrorism is that they readily admit much of it. The rest is fairly easy to unearth and that’s before one examines copious amounts of evidence from Wikileaks.
Wikileaks and other sources, including of course the common knowledge of Arabs from the Gulf to the Maghreb are also fully aware that Saudi Arabia is if anything an even bigger sponsor of terrorism than Qatar due to its greater size and wealth.