Emperior you means tribes holding hands and marching as 1? kind of like the million man march to washington? lol!!! i don't think that has ever occured unless under the guise of religion. For example Ahmed gurey had many tribes under his wing. Like many darods and habar yonis. But it was under the banner of islam and not neccessarily any emphasis on qabil harmony!!! Shabab is mimicking the same thing, like godane being the head of kismayo branch of shabab. However it is not hold hand session of tribal unity, but islamic unity!!!
The only time i see unity in somalis is when it was islam. Even when it was islam, not all tribes were united, i have never seen 100% all somalis united under any cause for that matter, be it islam or democracy or any system!!!
Like the sayyid for example, many tribes were against him, some where tribes were with him. Shabab same story. Somalis were never a nation sxb, they view their tribe as a nation from the days of history. They only make alliances with close knit families based on interest not really based on any love. It is just not apart of the culture!!! Alot of ppl think islam can unite somalis, but i doubt so. If great men like sayyid couldn't, how will some rag-tag shabab crew do it? That is why i support federalism because it gives us both unity and at the same autonomous states like our tribes have always been. It really is good system.