When we did a post on a building project by U.S. soldiers in Djibouti, Africa, we were surprised by how much attention the photos got.
The seemingly primitive "eco-dome" was made from bags, dirty cement, and barbed wire. But it triggered a number of questions.
There's a whole lot more to it.
Prompted by one reader's suggestion (thanks, PJ), here's a follow up on the igloo-like building and the reasoning behind the Army's involvement in distant African communities. 
The U.S. armed forces have a multitude of missions — from war fighting and Special Operations, to humanitarian and community building. Pretty much any job in the civilian world also exists in the military, such as being a chaplain, a medic, a water purification specialist, or a financial resource management analyst. Those are all military occupations.
So, the Combined Joint Task Force - Horn Of Africa has a civil affairs battalion. You could think of it as strategic philanthropy. It's been reaching out to African partners, coaxing along national stability and encouraging economic and social advancement.
But when the U.S. economy itself isn't doing great — and poverty exists here too — it can be frustrating for the American public to see its soldiers doing community projects in far-off villages no one's heard of.
African affairs analyst Lauren Ploch sheds light on why the U.S. would want to be entrenched in Africa:
The 1998 bombing of U.S. embassies in East Africa and more recent attacks have highlighted the
threat of terrorism to U.S. interests on the continent. Political instability and civil wars have
created vast under-governed spaces, areas in which some experts allege that terrorist groups may train and operate. The upsurge in piracy in the waters off the Horn of Africa has been directly
attributed to ongoing instability in Somalia. Instability also heightens human suffering and retards
economic development, which may in turn threaten U.S. economic interests.
"An Africa that is stable, participates in free and fair markets, and contributes to global economic development is good for the United States as well as the rest of the world," reasons the task force.
So that's where the "eco-dome" building comes into play. Designed to be a focal point for the Djiboutian village of Karabti San, it's going to be a school or a clinic that'll make the community stronger.
Using a combination of recycled and natural materials, the structure is intended to be sustainable and cheap to build. The Army says all the materials that went into the dome were sourced from the environment, or donated by non-government organizations.
Staff Sgt. Joshua Erickson calls it "Earth architecture". And the construction technique is perfect for under-developed communities.
"The idea came from a corporation called Cal-Earth out of California," said the team sergeant. "There was a situation in an area we couldn’t get materials to, and this could work perfectly for it."
The Soldiers built a prototype a few years ago at Camp Lemonnier and then pitched it to the Karabti San village. With guidance from the troops, the structure was mostly built by the villagers themselves, says the team.
"It’s fireproof, windproof, waterproof and earthquake- proof," said U.S. Air Force Capt. Kenneth Carmichael of the joint force.
He points out that it can withstand magnitude 8 earthquakes. It's not going to fall apart any time soon, and is a sound investment.
We've learned that people in the U.S. have been building their own eco-dome houses, since the concept originally came from California based on an Iranian-American architect's ideas. So there you have it:
Now see the incredible way U.S. soldiers built an eco-dome in Africa >
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