I mean, if the US goes ahead with boots on the ground the cost could be immense. Like Afghanistan, Iran is extremely mountainous. Unlike Afghanistan, Iran has a population of almost 100 million, spread across an area almost 3 times the size of Texas. And you can bet the Iranians paid very close attention to the tactics that worked in Afghanistan, on both sides. Tunnels and caves are extremely effective at nullifying air power, and tanks and IFVs don’t do well in mountains. That means you’re mostly left with grunts and artillery, fighting in terrain they don’t know, and which their opponents know intimately. And that opponent has been preparing for this fight for quite some time.