Is it possible to prepare for the unexpected? Could anyone have foreseen, for instance, a nuclear meltdown triggered by an earthquake-induced tsunami? Or a brutal band of transnational militants quickly capturing Iraq’s largest dam while attempting to establish a new Islamic caliphate? Perhaps not exactly, but that shouldn’t stop us from anticipating unlikely events, says Chad Briggs, a risk assessment expert and strategy director of consulting firm GlobalInt.

As presidents, prime ministers, and other policymakers from across the continent gather in Washington, DC, this week for the first-ever U.S.-Africa Leaders Summit, what are the issues to watch?

As global environmental change accelerates, understanding how population dynamics affect the environment is more important than ever. It seems obvious that human-caused climate change has at least something to do with the quadrupling of world population over the last 100 years.

World Population Day began in 1987 after public imagination was sparked by the idea that there could be 5 billion people on Earth. Today, we’re well past 7 billion and according to the latest UN projections, headed north of 9 billion by mid-century.

“You can look into the future a couple decades and get a very good idea about where countries are going,” said Richard Cincotta during a presentation at the National Defense University last summer – at least when it comes to demography.

Despite the threat posed by flooding and sea-level rise, relatively little attention has been paid to the potential for environmentally induced instability in coastal West African cities. However, current trends, including rapid population growth, land use patterns, and increasing climate impacts, suggest the costs of inaction in these urban areas are rising.

Last year, the International Committee of the Red Cross (ICRC) celebrated 150 years of their mission to “protect the lives and dignity of victims of war and internal violence.” Though this mission hasn’t changed in the past century-and-a-half, the nature of conflict and crisis response has. [Video Below]