Ethiopia's historical deal with Somaliland granting it commercial and military access to the port of Berbera is part of Addis Ababa's ambition to reestablish a green-water navy, but the deal's implementation will likely reshape the politics of the Horn of Africa and pave the way for protracted tensions with neighboring Somalia. On Jan. 1, Ethiopian Prime Minister Abiy Ahmed signed a Memorandum of Understanding (MoU) with Somaliland President Muse Bihi Abdi that set the basis for Ethiopia to recognize the breakaway region's independence in exchange for Somaliland granting landlocked Ethiopia military and commercial access to the Gulf of Aden port of Berbera. Somalia's government deemed the deal an act of ''aggression'' and accused Ethiopia of violating its sovereignty and territorial integrity. Egypt, meanwhile, expressed support for Somalia's territorial integrity amid sustained tensions between Cairo and Addis Ababa over the operation of the Grand Ethiopian Renaissance Dam on the Blue Nile....