The actual details of what happened are clouded in confusion and counterclaims, which is always the way in the days/weeks after these kinds of events. Very hard to draw any conclusions based on the little we know for sure.
Beyond that, it makes more sense to me for the Iranians to be behind it. While Bolton and perhaps Pompeo are up for a war with Iran, I don’t think Trump or the Pentagon are, and I think the Iranians believe the same. The sanctions are strangling Iran, Trump keeps going on about a deal, and a botched campaign against Iran would lose him the election. On the other hand, the Iranians have plenty of reasons to conduct this kind of operation. They have made threats which they now have to back up, they really don’t have many other options to hurt American interests in the region, save through their Iraqi, Lebanese and a Yemeni proxies.