I came across an interesting bit of analysis of Africom here, that includes this:
In a 2003 study entitled “U. S. Military Assistance for Africa: A Better Solution,” the Heritage Foundation argued, “Creating an African Command would go a long way toward turning the Bush Administration’s well-aimed strategic priorities for Africa into a reality.” Rather than engage Africa diplomatically, it is better to be diplomatic through the barrel of a gun. “America must not be afraid to employ its forces decisively when vital national interests are threatened.” Nevertheless, the U.S. will not need to always send its own soldiers. “A sub-unified command for Africa would give the U.S. military an instrument with which to engage effectively in the continent and reduce the potential that America might have to intervene directly.” The AFRICOM would analyze intelligence, work “closely with civil-military leaders” and coordinate training and conduct joint-exercises. In other words, the U.S. would make the friendly African military forces “inter-operable” not only with U.S. hardware but also with U.S. interests.
Assuming this is Bush/Cheney thinking, and it is pretty well spelled out by the Heritage Foundation, they are planning to use African military as agents protecting and furthering US interests, in other words, colonial armies.