Could that have something to see with the Uganda Oil exports?
But I do not see the US securing Somalia to allow China to build a large port in Kenya for their Sudan oil exports...
Or may be with weapon conrol in the area. If it's the case, invading Erithera could be easier. Ethiopia would love it!

By the way, the UN supported Somali government does control at the best 2 or 3 streets around the presidential palace and not even the Moga port or airport...
Sound crazy, can be funny!