It is not necessarily to be united states of Africa so as to be powerful, that could easily be achieved through adopting real democratic regimes that bring justice,equity, peace ,security, stability to the people and humanize them, as such the sustainable development will be realized and so the prosperity.
Such countries have the essentials of getting their ambitions achieved as well they have capabilities to establish very powerful confederacy or any form of alliance ..union such as EU..indeed not like the fragile,weak and sick African union or paralyzed Arab league