U.S. farmers have to deal with drought, insects, and West Nile viruses. So...why isn't there famine here in America?
All of the problems in Africa are caused by tin-pot dictators and U.N. meddling.
America is a huge country and US farmers work in different climates. Its rare to have simultaneous droughts in California, the Great Plains, the Ohio Valley and the Southeast.
However, we have an excellent irrigation and transportation infrastructure and so while a drought will drive up prices, food is still available. In Niger, most agriculture is rain-fed and there are very few reservoirs for irrigation. Being just south of the Sahara desert, its underground aquifers are weak.
If you look in your history books, you'll see that famines happened every 10 or 20 years on the East Coast in the 18th and early 19th century. Better roads and better shipping allowed for interstate commerce that made weak crops an economic issue, but not a famine issue.