[The Conversation Africa] This week Ethiopian Prime Minister, Abiy Ahmed visited neighbouring Eritrea, to be greeted by President Isaias Afwerki. The vast crowds that thronged the normally quiet streets of Eritrea's capital, Asmara, were simply overjoyed. They sang and they danced as Abiy's car drove past. Few believed they would ever see such an extraordinarily rapid end to two decades of vituperation and hostility between their countries.