I’m surprised it’s not already in place for rail freight. Pre-defined, well known routes, automatic right-of-way. You’d need some exception detection - spot things on the line or if any part of the train is behaving abnormally, but like cars you can “fail safe” - do an emergency stop if the computer or a remote operator decides that something has gone sufficiently wrong which you can’t do in a plane
Technology wise, aircraft are already 90+% automated - autopilot does basically the whole cruise phase, pilots are there to do the communication with ATC, manage the autopilot, and be hands on for taxi, takeoff and landing.
From a legal/policy perspective, the aviation industry is held to a much higher standard of reliability and safety than the automotive industry - the AI driven YOLO that companies like Waymo get away with. It’s not just that autopilot systems have to always work, it’s that they have to always behave in a predictable way.
“Well is there anything dangerous in there?”
“That’s classified, also, take a good look round at the building you are in and think about that question some more”
“Shit.”
I’m imagining a somewhat boring looking office/lab with a bunch of locked rooms.
“What’s in there?”
“Oh, it was Dr Simpsons lab in the 90s”
“Well what were they working on?”
“Don’t know, its classified”
“Well can we get rid of it?”
“I don’t know, it’s classified”
“Well who does know?”
“I don’t know, its classified”
Plus a bunch of old equipment and documents that are definitely secret and too valuable to just destroy, but no-one is entirely clear exactly how secret and valuable so it’s safer to leave it guarded in place than to try and move it
Most likely outcome (assuming you make it to Iran) is they make a big show of congratulating you and setting you up with a super lavish lifestyle that is totally not a compound that you are definitely allowed to leave if you want but why would you want to with all the people trying to kill you