Last I heard Iran doesn’t have a very large army. They might have lots of missiles and drones, but they wouldn’t be able to absorb a land attack. If Iran escalates too much, then the US will have to join and Iran knows that what will happen to them will be very similar to what happened to Iraq... if we still have all the missiles left to soften them up as we did Iraq.
For Israel to do a ground attack on Iran they'd have to get through either Muslim nations or the Strait of Horowitz, which Iran can easily defend. Basically Iran doesn't have to defend against a ground attack.
“then the US will have to join”
As I posted earlier:
“I assume everybody on Freerepublic is willing to send their sons (and maybe daughters) to die for Israel. I mean, surely they’re not advocating for sending other people’s children. I am not willing to do that, mine or anybody else’s. They will get my son over my dead body.”
Do you have children? Will you have them at the recruiters office Monday morning?