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As they debate how to tackle the threat of insurgency and unrest in Africa, Western leaders could do worse than to consider one of the most important, yet curiously underplayed, aspects of that troubled region -- the dangers of rapid, unchecked population growth.

It is no coincidence that in recent decades Mali's population has been growing at an unsustainable annual rate of around 3 percent. In other words, the average Malian woman has six children, while the country's population has tripled over the past 50 years and, according to the latest U.N. estimates, is set to triple again over the next half century.

Such a drastic rate of population growth rate has profound implications. In particular it means that, in an undeveloped and largely...