NO ONE can invade Persia … NO ONE will invade … it's drop the bombs … bring in the Special Forces to destroy what's left of the NUCLEAR FACILITIES … and get the heck outta 'Dodge' … hello
The terrain in Persia isn't conducive and besides as YOU point out there's 80 MILLION hostiles … do the 'nasty' and get out!
Israel wouldn't occupy … so why would the Americans? lol
Let the Persians get rid of the Mullahs and the IRGC … they're the ones keeping the 'good Persians' from success … hello