Khalid,
I know where your coming from but there is Habesha, Abbysinian and Ethiopian. Eritreans are more Habesha than the Amara, believe it or not. All this ethnicity is very new concept that was born no longer than 17th century and even then it was a low key thing.
Somalis will never understand Habesha because our understanding of origin is always tribalism and lineage. The Habesha are very different.
Habesha is not an ethnicity or group or some kind of genotype it was a nationality/citizenship and all of the people under Abyssinia were Habesha including south Yemenis.
As when we talk about relationship, the Tigre of Eritrea are related to the Biher-Tigrinya of now Eritrea and Tigray region. The Beja of Sudan is also related to the Biher-Tigrinya and the Tigre.
The Saho, Jeberti, Bilen are all related to the Tigre. The only people that are not Habesha are Rashaida, who are pure Arabs. Meles Zenawi himself, a Biher-Tigrinya, claimed that he was Yemeni but not Yemeni Arab but Habesha Yemeni (back in the days of Habesha/Abyssinia).
Remember Habesha is the name of the country which was referred to by Ancient Greeks and Arabs (Burnt people aka dark skinned).
Eritreans are more Habesha like you said before Aksum, the capital of Habesha was in whats Eritrea today.
The British and European division of Habesha people is all relatively new.
Eritreans know they are Habesha but they feel that they modern leaders of Abyssinia abandoned them and maltreated the founders. In fact, Eritreans consider themselves the nucleus of Habesha and many of them feel it was wrong for them to separate from Ethiopia.
The secession movement was began by the Muslims and later it was hijacked by the Biher-Tigrinya of Isais Aferwerki. Remember he is the nephew of Meles and his mother was born in Adwa like Meles.
Habesha have no true separation nor definition. It is only associated with the highlanders because of the leaders, scripture (Ge'ez), their old church, capitals, civilization.
From our point of view, the Adari do not seem to be Habesha because they arrived in the Horn of Africa only in the 16th century. But history claims otherwise. We need to hear from real Adaris.
The Harari, who refer to themselves as Gey 'Usu ("People of the City") are a Semitic-speaking people once thought to be descended from an Aksumite military outpost. Their language, Harari, constitutes a Semitic pocket in a predominantly Cushitic-speaking region. Originally written in the Arabic script, the Harari language has recently converted to the Ge'ez alphabet.