If Trump wants to send ground troops to Iran:

[Bluetus]

4. He will, of course. But I'm not sure that is even necessary

Iran has a large military, and they undoubtedly have well-defended positions. I don't see how 3500, 5000, or 17,000 (3 numbers of invasion troops I have heard) can accomplish much of anything unless there are some specific special operation missions.

Just look at the map. They have water on the entire southwest border and that is so heavily armed that the Strait of Hormuz is impassible. Everywhere else, you have borders with nations not particularly friendly to either the US or Israel: Turkey, Azerbaijan, Turkmenistan, Afghanistan. The only bordering countries where the US might be allowed access are Iraq and Pakistan. I can't see a ground assault coming from Pakistan. That's the wrong end of the country.

So what are we going to so, roll in 500 tanks from Iraq. Good luck with that. That would be a killing field. Can anybody think of any sensible ground invasion strategy?