Here is the tactical problem:
Iran is well aware of Israel’s (rightful) intentions and America’s weapons, and have up-armored every critical process in their nuclear weapons program.
Tunneling is something that Iran has always done better than any country in the world, throughout history, it’s an engineering fact.
Israel’s goal is to attack, not to necessarily succeed. A show of strength at a minimum.
America has a different challenge, we cannot participate in an attack that doesn’t win. If our bunker-busters don’t work, we lose the credibility of that weapon system.
The world will then know that anyone, N Korea, Venezuela, Cuba, Myanmar, Pakistan, etc can hide evil underground.
Our military planners doubt the bunker-busters will work.
De-mystifying ground penetration bombs ends their diplomatic and strategic use.
OK, everyone will know how deep to dig.
And...Iran will learn from any failed attack that it cannot be stopped by Israel or America. They will bray like a pack of mules at the world...and be believed.
I believe that Iran wants to be attacked.
Small tactical nuclear weapons.