Politicians must be finding it harder and harder to work out in the wider sustainability agenda what still falls in the ‘loony’ category (as climate change once did) and what now falls in the ‘emerging and increasingly mainstream’ category – which they better get their heads around for fear of appearing out of touch.

The speed with which issues move from the former to the latter must be mind-boggling for them, persuaded as most of them still are that there is nothing fundamentally wrong with today’s model of ‘progress through growth’ that can’t be sorted out by a few timely touches on the tiller. Bless!

For instance, only a couple of years ago, if you so much as mentioned the need for Ministers and officials to think much more seriously about ‘food security’ (in other words, how this nation will secure access to enough food of the right kind at the right price in the future), you were definitely consigned to the loony category.

Indeed, Defra and Treasury combined forces in 2005 to produce a ‘Vision’ for the Common Agricultural Policy which oozed contempt for any such lame-brain recidivism: food security may have been a big deal after the Second World War (when the Common Agricultural Policy became our principal response), but today’s global food industry is deemed to be totally immune to any such pressures.

It all looks very different now – and although Treasury is unlikely to be found giving voice to such an heretical concept, Defra is beginning to think much more seriously about food security. This may have something to do with the highest-ever recorded rises in the price of food in 2007, or the fact that prices in various food commodity futures markets are climbing higher and higher, or that food imports into China are rising every year, or that harvests around the world are being seriously impacted by extreme weather conditions (which you may or may not link directly to climate change, depending on how cautious you are in pointing out cause and effect in such phenomena), and that ill-thought-out strategies for converting land to produce biofuels rather than food are already having an effect on food prices in different parts of the world.

So watch out for further developments on this front within Defra – if not in Treasury, or even in the FCO, where David Miliband has just junked sustainable development as one of the Foreign Office’s over-arching objectives. But more on that later!

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