Op made his question really clear and I feel many of us went a little over board.
The question is if a unified language can solve tribalism in our country, not whether tribalism can solve our bad economy.
China, literally one of the most developed countries in the world has over 700 languages and a former president of theirs forced everyone in the country to learn a particular Chinese language which was Beijingese . It evolved over time and became the standard Chinese language over 92% of their population speak. That didn't mean that the remaining 899 other languages were lost or suppressed . Today we still very much hear of the Cantonese, the mandarin, the taiwanese and many others, cause even in their unification they protected and preserved their culture.
.....sorry for the drift.
Anyways, the point I'm trying to make is that togetherness plays a very major role in the growth and development of a group of people. One crucial part of togetherness is to be able to communicate in the same dialect. To be able to speak another man's language doesn't mean your losing your identity, it just means your strengthening bridges and relationship.
Today in china there is very much still diversification and unity which makes them strong, but in our country it's only diversification I see, no unity in any form. After graduating from the University we go for NYSC, which was established for the sole purpose of unity in diversification but after everything we still end of casting votes for people during elections that we know very much are incapable of the duty and responsibility of leading us, mainly because why? were of the same tribe, that's not unification at all.
So, in my own opinion a unified language will very much solve the problem of TRIBALISM in Nigeria and help us to individually stop categorizing ourselves under tribes and just see ourselves as one Nigeria.
Thank you so much for adding clarity to my post. Thank you for being detailed and even siting an example of where my suggestion actually worked. A lot of people are just too emotional in this board. We all know that tribalism is a problem that make us rarely speak with one voice in this country; if tribalism is solved, almost thirty percent of our problems would have been solved. Many people commit all manner of crimes across the country simply because they know that taking them to the police will be a furtile effort because their tribesmen dominate the police and will release them the next day if you take them there. Check the arrogance of cattle headers and truck drivers, you will see how tribalism make them bold in doing the wrong things. The same goes for politics... like you said, we have diversity bit no unity so we need more things that unite us more than those that divide us.