Climate change is an urgent national security issue. So says a recent National Intelligence Assessment and an influential group of retired military officers and defense experts at the Center for Naval Analysis, a nonprofit policy analysis group.
Left unchecked, they say, global warming will sow political instability and conflict in already-fragile parts of the world, places such as Pakistan, the Middle East and Africa.
“We’re a global society now. We can’t isolate ourselves from that kind of thing,” said former Sen. John Warner, R-Va, during a recent visit to St. Louis.
Mr. Warner was a panelist at a forum on national security, energy and climate change sponsored by the Donald Danforth Plant Science Center.
Mr. Warner and retired Vice Admiral Dennis McGinn, another forum panelist, said climate change and energy security already are straining the nation’s military capability. Those stresses probably will increase.

There are a lot of ways to think about global warming: an environmental problem, a technological challenge, a moral issue. It’s all of that and much more.
A 2008 National Intelligence Assessment concluded that climate change will affect the United States and cause the existing problems of poverty, environmental degradation and ineffective leadership in other countries to worsen.
Scientists already are predicting that climate change will alter rainfall patterns and temperatures around the globe. That threatens agricultural production for large numbers of desperately poor people.
We can’t expect them to quietly starve. Crop failures in Africa probably would produce huge waves of migrants to Europe. Similar failures in Central or South America could send millions more fleeing to our shores. Competition for scarce resources — oil, clean drinking water and food — would increase.
All of that makes it more likely that the U.S. military would be called into action, either to provide humanitarian assistance or to go into combat.

The threat isn’t just theoretical. We’re already paying a price for the nation’s — and the military’s — dependence on oil.
The United States consumes 25 percent of the world’s oil production but controls just 3 percent of the supply. Even if we drilled our every drop, world markets would remain tight and prices high.
The U.S. military is among the nation’s largest oil consumers, fueling everything from ships and aircraft to tanks and trucks — even generators at military installations around the world.
Our insatiable thirst for oil sends billions of dollars overseas every day, enriching regimes that oppose us. Russia’s resurgence largely is financed by oil revenue. So is Iran’s.
But that’s only part of the price, as a new report by the Center for Naval Analysis points out. Protecting oil supplies for ourselves and our allies involves American forces deployed around the world at enormous cost to taxpayers.
It also means we do business with repressive regimes, which undermines our diplomatic leverage and foreign policy objectives.

Congress is debating a bill that would limit greenhouse gas emissions and encourage development of alternative energy sources. Most people see the so-called cap-and-trade bill as an environmental measure, but it has major implications for national security.
Cutting our dependence on foreign oil would help avoid the worst consequences of climate change and increase energy independence. It would help spur development of technology to reduce the military’s energy demands and enable it to project force more efficiently and less expensively.
Global climate change poses too great a threat — to the environment, yes, but also to national security — for us to fail to act.
Congress should protect America by passing cap-and-trade bill.