Age: 54
Occupation: President of Nigeria
The twin imperatives of trying to end a bloody northern Nigeria Islamist rebellion led by Boko Haram and dismantle the fuel subsidies that are one of the country's main sources of corruption (but are also, awkwardly, generally popular for keeping gas prices low) requires bold leadership of Jonathan, who is finishing his first year in office. Whether Nigeria descends into civil unrest, civil war or splits, or whether it reforms and Africa's sleeping giant finally awakens, depends foremost on him.