Hm. It's not in their interest to openly take such actions in such a way that their responsibility is beyond doubt, though.
The problem being that Iran did have to emphatically reject all responsibility in public, so as not to damage its relationships with Europe, Japan, China and other countries other than the US. Whatever the actual truth, it's kind of hard to project power or rally your population behind something you're denying you actually did.
But I guess it's a bit like the way Iran keeps piously denying that they would ever develop or use something as horrible and un-Islamic as nuclear weapons, insisting that they want those nuclear facilities only for civilian purposes and because it's humiliating to be blocked from such progress by foreigners. In some ways it's better for them to be in this kind of position, close enough to being able to develop nuclear weapons that foreign governments have to take them seriously, but without actually having them, which allows them to keep claiming the moral high ground (successfully so for some audiences, not so much for others).