The Organization of African Unity (OAU) transformed itself into The African Union (AU) back in 2002. In spite of all the ills afflicting Africa and the opportunities they present, neither the OAU nor the AU can be credited with having created sustainable solutions that stood the test of time.
The concept of a coherent union that can implement cross country goals, although nice on paper, seems too far fetched. Given the divisive and often violent eruptions within individual countries, the idea that the 53 countries can stand as a single force to reap benefits that will help mitigate Africa's immense problems is wishful thinking at best.
Zimbabwe probably embodies all that is wrong with the AU. I don't think there will be much disagreement among objective observers that Mugabe has single-handedly destroyed the country. If the AU is to have any credibility at all, people like Mr. Mugabe must be expelled from its membership first. It is far better to start with 10 functioning countries and grow the membership slowly as more and more countries come to accept some core principles that are necessary to advance Africa's interests and future viability. Otherwise, having a leaky tent of 53 countries, some who came to power through killings, serves no purpose at all.