You are right on the Taliban but in the case of Tigray you are missing the bigger picture. The problem is two fold. The first is the old guard in Tigray who want the status quo whereby they benefitted the most from the ethnic states created after the fall of Mengistu. Ethiopia was basically turned into a group of nation states. Abby was trying what Ruto has been trying in Kenya i.e to make a united country with support of the younger generation but the old guard especially in Tigray with powerful allies in western capitals dont want to lose their power. Tigray was /is very much like Somaliland inside greater Somalia. The second and biggest problem is external first being with Egypt and Sudan because of the GERD of which there are records as far back when Morsi was president in Egypt discussing destabilizing Ethiopia to stop the construction. The second is the greater world geopolitics between the superpowers. China is very invested in Ethiopia and if it goes well then Addis being the AU headquarters will be a springboard to greater influence in Africa. You have to see the mischief from this geopolitics. Imagine ISIS in Mozambique of all places where even blending in is very difficult because of religion and ethnic mix. But of course with money you can create anything. The huge gas reserves will pay for it.