The Climate and National Security

Published: August 17, 2009

One would think that by now most people would have figured out that climate change represents a grave threat to the planet. One would also have expected from Congress a plausible strategy for reducing the greenhouse gas emissions that lie at the root of the problem.

That has not happened. The House has passed a climate bill that is not as strong as needed, but is a start. There are doubts about whether the Senate will pass any bill, given the reflexive opposition of most Republicans and unfounded fears among many Democrats that rising energy costs will cripple local industries.

The problem, when it comes to motivating politicians, is that the dangers from global warming — drought, famine, rising seas — appear to be decades off. But the only way to prevent them is with sacrifices in the here and now: with smaller cars, bigger investments in new energy sources, higher electricity bills that will inevitably result once we put a price on carbon.

Mainstream scientists warn that the longer the world waits, the sooner it will reach a tipping point beyond which even draconian measures may not be enough. Under one scenario, atmospheric concentrations of greenhouse gases, now about 380 parts per million, should not be allowed to exceed 450 parts per million. But keeping emissions below that threshold will require stabilizing them by 2015 or 2020, and actually reducing them by at least 60 percent by 2050.

That is why Rajendra Pachauri, the head of the Intergovernmental Panel on Climate Change — no alarmist — has warned that “what we do in the next two or three years will determine our future.” And he said that two years ago.

Advocates of early action have talked about green jobs, about keeping America competitive in the quest for new technologies, and about one generation’s moral obligation to the next. Those are all sound arguments. They have not been enough to fully engage the public, or overcome the lobbying efforts of the fossil fuel industry.

Proponents of climate change legislation have now settled on a new strategy: warning that global warming poses a serious threat to national security. Climate- induced crises like drought, starvation, disease and mass migration, they argue, could unleash regional conflicts and draw in America’s armed forces, either to help keep the peace or to defend allies or supply routes.

This is increasingly the accepted wisdom among the national security establishment. A 2007 report published by the CNA Corporation, a Pentagon-funded think tank, spoke ominously of climate change as a “threat multiplier” that could lead to wide conflict over resources.

This line of argument could also be pretty good politics — especially on Capitol Hill, where many politicians will do anything for the Pentagon. Both Senator John Kerry, an advocate of strong climate change legislation, and former Senator John Warner, a former chairman of the Armed Services Committee, say they have begun to stress the national security argument to senators who are still undecided about how they will vote on climate change legislation.

One can only hope that these arguments turn the tide in the Senate. Mr. Kerry, Mr. Warner and like- minded military leaders must keep pressing their case, with help from the Pentagon and the White House. National security is hardly the only reason to address global warming, but at this point anything that advances the cause is welcome.

A version of this article appeared in print on August 18, 2009, on page A22 of the New York edition.