About the meaning of "tribe" in Africa:
1) To me, the key semantic objections lie in how "tribe" and
"tribal" got incorporated into late 18th, 19th and 20th century
cultural evolutionary schemata. "Tribal" was a stage societies
evolved through (often associated with pastoralism - cf. 12 tribes of
Israel). For some, barbarians came in tribes, savages in smaller
groups, and some tribes could become kingdoms or empires (e.g.
ancient Germans; Zulu & Ashanti. There's a Harvard-published article
from 1910 or so comparing Zulu & ancient Spartan military
organization).
Europeans recognized their ancestors has having had tribes, but
centuries before, and they had evolved out of them. Africans had
tribes in the present. Perhaps in centuries they wouldn't.
Meanwhile they would be primitive, savage, in need of civilizing etc.
George Stocking's *Victorian Anthropology* is good on all of this.
It is the association of "tribe" with ostensible primitiveness and
savagery which is the heart of the problem. Yugoslavians become
"tribal" when they start committing genocide, meaning they are
regressing to a more primitive state, supposedly. Our media fail to
acknowledge that this is civilized savagery, produced by an urbanized
industrial culture (like the Nazis industrial death camps), just as
the media emphasize ostensibly timeless ethnic conflict in Rwanda
rather than use of radio to mobilize genocidal violence.
2) Africans who speak English use the word "tribe", as Harold
Marcus observes. In isiZulu, the word is "isizwe", in siSwati it is
"sive". A dictionary will give you as a translation "tribe" or
"nation". The ANC called its army Umkhonto weSizwe - Spear of the
Nation, not Spear of the Tribe, to be sure. Swazi political leaders
have been quite definite for a century and more in translating sive
as "nation", having come to understand that "tribes" had lesser
claims to sovereign independence in English idiom.
How much African use of "tribe" in English reflects either what they
were taught in school, or what they think will be understood in the
expectations of foreign English-speakers?
But maybe that's too simple. In many multi-ethnic African states,
efforts at nation-building try to define the nation as a collectivity
identified with the state. So maybe people turn to "tribe" to speak
in English of other identities, more localized, or split by
"national" boundaries, or of a linguistic/cultural nature, arguably
of deeper historical roots, as against the "nation".
I would still be very surprised if the indigenous terms for those
identities, and the groups they assert, carry all (or any) of the
pejorative connotations attached to the term in English. In that
case, "tribe" is a poor translation leading to misunderstanding of a
crucial real phenomenon.
Conversely, how often are African uses of "tribe" intended to
discuss a form of identification regarded as destructive or
unhealthy?
There does seem to be a strand of usage by some African
intellectuals on the internet who want to re-appropriate the term to
mean something like "indigenous collectivity, organized according to
indigenous values and principles." Such a use has a lot of history
to fight against.