I'm U.S. and I agree that we wouldn't nuke. For one thing, we don't have to because there are many other options besides armed conflict of any
sort, even now, with all the saber rattling. For another, there is the built in "proportionality" concept in the laws of war for modern, UN
sanctioned warfare. The U.S. went to some trouble to get UN approval in Afghanistan to connect non-state actors (AQ) to state actors (Taliban) and
attack them both. They were even using the rules of preemptive attack before that to attack AQ. If the Iranians attempt to close the Strait, then we
can respond proportional to the threat, clear it, and try to keep it open - I doubt seriously that it could be used as a pre-text for open warfare
with Iran unless preemption, e.g. destroying threatening missile batteries comes into play. You can see the runaway logic in this, "Gotta open the
strait, can't do it without ships in there, ships are threatened by missiles, gotta kill the missile launchers, they're protected by ground to air,
gotta kill that...etc. etc."
There is a gigantic corpus of international law that governs how these things play out in a modern world. The bigger threat I believe is the
possibility of ungoverned cyber warfare between non-state Iranian actors, sympathetic quasi-non-state attackers all over the world, and retaliatory
strikes by sympathetic Western actors. It really is the wild west out there. There are many posts on ATS about the capabilities of various national
cyber forces, suffice it to say, if it's connected to the internet, it is vulnerable whether it's something big or something small. However, these
are not the most likely "first responders" on the cyber battlefield nor would they be because their entry into a conflict would constitute an
"armed attack" and consequently allow for a broader application of the laws of war. Rather, non-state cyber attacks, possibly aided by information
from state actors, are the more likely scenario. These attacks could have dramatic impact. For instance, if a state actor wants to put the U.S. in
its place without direct conflict, they could pass information to non-state actors, e.g. organized crime hackers, who could then apply their craft in
a surprise attack on U.S. forces. Who does the U.S. attack in response? How do they find out who did it or who received the critical information?
If a carrier is sunk because of something like this, and the U.S. bombs Iran when non-Iranian, non-state actors are involved, that will be a tragedy
on both sides. So, this is a very, very tricky situation and the precedent of involvement from non-state actors has already happened.
Don't trust me though, verify and read the refs below:
Botnets and C&C for hire make a cyber conflict the most likely IMHO. The degree to which non-state actors can perform autonomously will determine its
success. If they're linked to state actors, then "armed attack" comes into play and then it's probably bombs away time. I hope we don't get