The Cold War shaped world politics for half a century. But global warming may shape the patterns of global conflict for much longer than that -- and help spark clashes that will be, in every sense of the word, hot wars. We're used to thinking of climate change as an environmental problem, not a military one, but it's long past time to alter that mindset. Climate change may mean changes in Western lifestyles, but in some parts of the world, it will mean far more. Living in Washington, I may respond to global warming by buying a Prius, planting a tree or lowering my thermostat. But elsewhere, people will respond to climate change by building bomb shelters and buying guns.
"There is every reason to believe that as the 21st century unfolds, the security story will be bound together with climate change," warns John Ashton, a veteran diplomat who is now the United Kingdom's first special envoy on climate change. "The last time the world faced a challenge this complex was during the Cold War. Yet the stakes this time are even higher because the enemy now is ourselves, the choices we make."
Defense experts have also started to see the link between climate change and conflict. A 2007 CNA Corp. report, supervised by a dozen retired admirals and generals, warned that climate change could lead to political unrest in numerous badly hit countries, then perhaps to outright bloodshed and battle. One key factor that could stoke these tensions is massive migration as people flee increasingly uninhabitable areas, which would lead to border tensions, greater demands for rescue and evacuation services and disputes over essential resources. With these threats looming, the U.N. Security Council held a precedent-setting debate on climate change in April 2007 -- explicitly casting global warming as a national security issue.
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Such displacement can arise either suddenly or slowly. The growth of the Sahara, for instance, took many millenniums; many thousands of years ago, people were slowly nudged out of the inland region of northern Africa and into such great river valleys as the Nile and the Niger. Over time, incremental but prolonged rises in sea levels will also gradually uproot hundreds of millions of people. But sometimes the displacement happens with shocking speed: Just think of the deadly hurricanes Katrina and Rita, which together drove millions of people to suddenly leave Louisiana, Mississippi and Texas. As global warming and population growth increase, we could see far deadlier storms than Katrina. In 1991, a cyclone in Bangladesh displaced 2 million people and killed 138,000.
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