The Ministry of Defence is not known for its concern for the environment. Nevertheless there is one group of people at the MoD very interested in climate change and, in particular, catastrophic climate change - namely the strategic planners.
They know that the armed forces can react and adapt very rapidly to limited changes in the strategic environment. What the forces cannot do is meet a fundamentally different kind of challenge from the one with which they are equipped to deal. In 1939, the British army was the wrong size, had the wrong equipment and, most dangerously, the wrong doctrine to meet the threat from Germany.
That is why the MoD's planners insist on trying to look ahead several decades. Of course, much of this futurology is speculative, subjective and all too frequently wrong. But one trend on which there is ever greater scientific certainty is the impact of climate change.
In the 2003 defence white paper the MoD argued: "Religious and ethnic tensions, environmental pressures and increased competition for limited natural resources may cause tensions and conflict - both within and between states. The UK may not remain immune from such developments."
More recently in an MoD discussion note, climate change was one of four themes identified as strategically important: "The combined effects of increased global human activity, economic output and population growth look likely to intensify pressure on the environment and food, water and energy resources. This trend will be exacerbated by urbanisation and the creation of 'mega-cities', while industrialisation and personal expectations in developing countries will strain all resources." In Darfur, environmental pressures (through lack of water) have already contributed to generating an internal conflict that is rapidly becoming regional. In Afghanistan, a recent six-year drought has helped to impoverish people, making young men more willing to accept cash inducements to join the Taliban and farmers more likely to grow opium.
These influences are small compared to what may be the start of far more disturbing changes. What happens if, or when, sea levels rise and force millions from their homes in Bangladesh, the Nile Delta and the coastal regions of China? What happens when floods, landslides and storms regularly leave millions unemployed and homeless?
Many in the MoD strongly believe that these are not just environmental or development issues, but vitally important security questions that need to be given far more serious consideration, both within government and by the public. Naturally, failed states and international terrorism are significant current threats to security, but that does not excuse us from focusing on future threats.
There are two ways in which the UK's armed forces will have to respond to challenges presented by climate change.
First is disaster relief and humanitarian assistance. In principle, civil organisations could play a bigger role in disaster relief. Sadly, so far none has been willing to stump up the very large amounts of cash required to gain the military's ability to provide rapid response, or operate in very difficult terrain.
The second and more difficult task that the armed forces may face is the potentially huge security challenge created by climate change. No one knows how this will manifest itself. As more and more people in Bangladesh seek sanctuary from rising sea levels, will the tensions created lead to a collapse of the state and war with India? Will poverty caused by growing water shortages in North Africa boost support for international terrorism? Will floods and environmental degradation in China lead to economic collapse and a rise in nationalism?
In an ideal world, the best and cheapest methods of dealing with these scenarios would be non-military. Appropriate diplomatic action and well-targeted humanitarian assistance can do much, and these need to be well funded. But we do not live in an ideal world, and the Department for International Development and the Foreign Office may fail to meet these challenges. One way or another, Britain's armed forces will become involved - in the best scenario as part of a UN peacekeeping force, but possibly having to take more drastic action to protect our security interests.
Climate change is already making the world more dangerous and no one knows how much more dangerous it will become. A Labour government which ignored this growing threat would be repeating the tragic mistake of George Lansbury in his opposition to rearmament in the 1930s.
Josh Arnold-Forster was special adviser to John Reid at the Ministry of Defence from 2005 to 2006
Countdown to climate disaster
8 out of 10 of the warmest years since records began in 1860 have occurred in the past decade
60,421km2 annual rate of decline of sea ice
43cm estimated maximum rise in sea level by the year 2100
100 million combined population of the 13 most populous coastal cities in the world
11.55pm time on the Doomsday Clock, now set closer to midnight as a result of global warming
Research by Mosarrof Hussain
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