There are increasing reports of a US military build up of potential ground forces heading towards Iran. Trump’s 5-day truce is looking like a ruse to shore up defenses among Gulf allies and and bomb Iran’s offensive capabilities before than can be turned against Gulf infrastructure.

So what’s the plan?

All the speculation is about marines capturing Kharg Island and the administration itself has hinted at it but the logistics are brutal. Parachuting in strands the soldiers and to sail an amphibious ship even close, it would need to pass the Strait of Hormuz and 1000 km of hostile seas. Resupply would also be a problem. The mission has been ‘leaked’ by Axios but that outlet is increasingly looking like a White House misdirection mouthpiece.

Invasions from Iran’s west are nearly impossible as it’s all mountainous terrain, the kind fought over in the Iran-Iraq war for 8 years with nearly zero progress. Elsewhere in the country is also brutal as the country is 65% mountainous and hardened.

The softest part of Iran is eastern border with Pakistan and — maybe not coincidentally — that’s where White House envoy Steve Witkoff is right now. That area is a desert wasteland, very sparsely populated and where some of the hottest temperatures ever recorded are. Near the coast is a wide, arid plain of hard-packed sand and gravel, easy to cross.

The prize in that region — as I highlighted yesterday — is Chabahar. That’s Iran’s only open-ocean port. It’s just 150 km from the Pakistan border and the US carried out fierce attacks on it an the nearby Konark Naval Base.

If US forces can seize Chabahar, they can use it as a staging area for a ground invasion towards the Strait of Hormuz, which is 650KM away.

Seizing Chabahar is logistically do-able with the roughly 10,000 soldier force that’s amassing in the region and that’s why it’s something to put on your radar. In terms of the map, taking much of that province would also show a big win for the US in square miles. But the task would get considerably more difficult as forces move west as the only infrastructure is a narrow highway along the coast. It’s like a long canyon where one side is a mountain and the other is the sea. It would be vulnerable to ambushes and the bridges would be destroyed, something that Iran has surely game planned.

If you can get to the mouth of the Gulf of Oman it gets more mountainous and more treacherous but if the US can establish itself at Chabahar, it could improve their negotiating position and cut off a portion of Iran’s economy.

In terms of markets, the reaction would be ugly. A ground invasion would signal a long potential war and undo the positive moves from Trump’s talk that the war was ‘winding down’ and it would forever damage his credibility in talking about ending the war. It could also trigger a full-out assault on Gulf countries and energy infrastructure. For markets, it would start to look like a replay of the Iraq war and a potentially months-long effort to re-open Hormuz.

This article was written by Adam Button at investinglive.com.