This thread is titled Whats happening in Iran, and getting back to that a bit -
Based on how I view Trump and his mentality, I think it is very unlikely that the carrier groups will simply withdraw without having fired a shot. The only way I can see this happening is if the Iranian regime publicly humiliates itself with overt concessions to Trump and makes no effort at any face-saving on their part - and perhaps the only way to avoid this is if they actually leave Iran in short order - both of these notions are fanciful, imo.
I think US casualties caused by Iranian actions are also unlikely - there may be deaths resulting from accidents during airstrikes but I doubt the Iranians will shoot down any aircraft or be able to put any fire on US vessels. I'm no kind of military expert, I'm just going by recent history when I say this.
Bush The Younger lied to us about WMD's - Trump isn't even bothering to do that much. It may not be obvious to the non-US posters here, but I claim he has made absolutely NO domestic case for any imminent threat justifying military strikes against Iran. That is even further than he went with Venezuela where he claimed that smuggled drugs represented an imminent threat to national security - laughable perhaps, and at the time I thought the bar for justification of force couldn't get lower, but now here we are and the bar is indeed lower, with not even a laughable pretext at imminent threat being offered.
So where does that leave the US, I wonder. I certainly hope it adds momentum to his popularity dropping, and boosts the election chances of anyone running for congress who is asking to be elected to oppose his policies. I also hope that when the imo now inevitable strikes do happen, it peels away a few more House R's and congress will make further aggression explicitly illegal - but that is probably also fanciful. I echo your sentiment,
@fresh_42, for no Iranian casualties, but how could that end up being the case?
or to steal oil money from Iran
He may have some notion that if the current regime falls, he can justify lifting sanctions and US oil companies will start operating there. I really hope that is not his thinking - if the US topples the government there the resulting chaos would be unimaginable.