Nigeria is paying for it's own Grid (as an example). They have a population of about 130 Million people, they are about twice the size of Texas.
They certainly have Huge cities already lit up, Lagos, Calabar, Port Harcourt, Abuja, Kano, Enugu, Sokoto, Ibadan, and lesser towns like Ilesha, Oyo, ife, ...and many many more.
They Have a huge Hydro-electric Dam at Kainji, and they have Coal and Oil burning Facilities.
Nobody is forcing Obama or the US to invest anything. However if they chose to invest, the expectation that what Africa needs is substandard PV power is annoying, and this is almost exclusively the message I get from renewables fans.
Africa wants real power, enough to supply home grown automobile manufacturing, Textiles, Plastics, Iron and Steel Manufacturing. Africa for short wants what the West already has, and people suggesting that they should settle for PVs to light up some LEDs and charge laptops is riddiculous.