Thinking a bit about the USN...

[Olefin]

Having Guam be intact actually makes sense in a lot of ways - there are a lot of USN bases that werent hit by nukes - the most glaring example is seen in Last Submarine. (i.e. the sub base in CT)

And a lot of targets that should have been vaporized werent in the game - for one San Antonio shouldnt have Russians sitting in it unless they are glowing. That ring of air bases and supply depots around it basically screams NUKE ME!! and yet the city is intact.

I totally buy into the breakdown of their C3 system leading to targets that either got overlooked or missed or the missile shot down not being engaged again.

With their satellites gone, most of their communications shot and Moscow gone they may have just had to rely on stuff like "Do we have a record of the sub acknowledging the attack order against Guam? It did, well then it must have been destroyed. Confirmation of the launch and that we hit the target? Heck I cant confirm anything past line of sight with how screwed up our communications are. if the sub got the message then its been taken care of. Ivan, mark Guam down as destroyed."

And thus Guam survives the war.