This approach isn’t unique to security professionals – from time immemorial grandmothers have been admonishing their offspring that prudence is the better part of valor.  And few among us are so risk tolerant that we’d rather ignore a threat than take steps to protect and prepare ourselves as best we can.  We don’t have fire insurance because we think our homes will burn down, we have fire insurance because we know there is a risk of a home burning and the consequences are too grave to ignore.

On the national security front, risk management approaches have allowed countries to plan and act in the face of even the most terrifying threats.  For example, the United States’ nuclear deterrent during the Cold War —a response to the uncertainty of an arms race with a mysterious and potentially deadly enemy in a nuclear age—worked. It was expensive and included redundant measures, but it prevented a much more terrifying and unquantifiably damaging result – nuclear war.

On the other hand, France’s failure to accurately assess the threats posed by Germany’s abilities in the lead up to World War II shows what can happen when a nation facing uncertainty and internal political squabbling fails to analyze the full suite of risks and make a comprehensive effort to manage them. In that case, France ignored the risk that German armored maneuvers could make the massive investment in the Maginot Line obsolete.

When it comes to climate change, uncertainty must not be a barrier to action. Uncertainty doesn’t mean we know nothing; just that we do not know precisely what the future may hold in a given place at a given time. But we have a good handle on what the risks of climate change look like. Will the oceans rise by two feet or six? Will global average temperatures rise by two degrees, or five? Other weighty public policy decisions– from military procurement to interest rates to financial system regulation – are taken under far higher uncertainty than exists when it comes to climate change science.

It is time to re-boot the conversation about global warming, to focus not on politics but on the risk to global security that climate change represents. Like other such threats—nuclear proliferation, terrorism or failing states-- climate change requires responsible planning that takes into account the full range of uncertainty. It requires that our leaders truly explore what level of risk we are willing to take and put in place effective strategies to manage the risk to us all.

Nick Mabey is chief executive of E3G, an international nonprofit. He was a senior advisor in the U.K. Prime Minister’s Strategy Unit, leading work on energy, climate change, and countries at risk of instability.

Jay Gulledge, PhD, is the director of the Science and Impacts Program at the Pew Center on Global Climate Change, and a non-resident senior fellow at the Center for a New American Security.