Here are key facts about the tense interplay of relations in the Horn of Africa, where Somalia has long been a battleground for various players' interests, particularly those of Ethiopia.
|Somali government troops receive support |
and tranining from Addis Ababa [AFP]
* Ethiopia and Somalia have been rivals throughout history, and memories of the 1977-78 Ogaden war between the two are still fresh.
Fought against a backdrop of shifting Cold War alliances, Ethiopia's army crushed Somali troops who tried to lay claim to the Ogaden region with the vision of recapturing ethnically Somali territories outside Somalia.
Ethiopia had seized the Ogaden in the early 1900s in what Somalis viewed as a colonialist expansion by a Christian empire.
* Ethiopia has not hesitated to send troops into Somalia to attack Somali Islamist movements, wary they could stir up trouble in the ethnically Somali regions on its side of the border.
Since the Islamic Courts took power in June after kicking US and Ethiopian-backed warlords out of Mogadishu, Addis Ababa has warned it would crush any Islamist attack.
* The current fight is a repeat of history with the same players involved. Several times from 1992 to 1998, Ethiopian soldiers attacked al-Itihaad al-Islaami, a Somali group the US has put on a list of organisations linked to terrorism.
|Islamic Courts fighters are bitterly |
opposed to Ethiopia's presence
Sheikh Hassan Dahir Aweys, Islamic Courts leader, led its military wing at that time. Abdullahi Yusuf, the current interim President, then a warlord with Ethiopian money behind him, led his militias against al-Itihaad in that period.
* A report to the United Nations on arms embargo violations says Eritrea has given weapons and training and sent about 2,000 troops to back the Islamic Courts, to frustrate the Ethiopian-allied interim government.
Eritrea denies the charge, though makes no secret of its hatred of Ethiopia over their still-unresolved border dispute, which led to a 1998-2000 war.
* Military experts estimate Ethiopia has 15,000-20,000 troops inside Somalia.
Source: Al Jazeera and agencies