I doubt the Iranians will do anything particularly bothersome.
Up until now, US retaliation has been either diplomatic, or shooting up a couple of camels with a cruse missile. Trump didn't do that. He attacked a person. Now, if you are in the business of pissing off the US, and all the US does in response is bluster or a few explosions in the desert, there's not much cost to creating mayhem to piss off the US. If, on the other hand, high ranking individuals get killed in response? Might think again about how you're going to "retaliate".
