here's the article (cut & paste, you need an account to view it online at 
economist.com):

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"You don't have to wait for government to move... the really fantastic 
thing about Fairtrade is that you can go shopping!"  So said a 
representative of the Fairtrade movement in a British newspaper this year. 
Similarly Marion Nestle, a nutritionist at New York University, argues 
that "when you choose organics, you are voting for a planet with fewer 
pesticides, richer soil and cleaner water supplies."

The idea that shopping is the new politics is certainly seductive. Never 
mind the ballot box: vote with your supermarket trolley instead. Elections 
occur relatively rarely, but you probably go shopping several times a 
month, providing yourself with lots of opportunities to express your 
opinions. If you are worried about the environment, you might buy organic 
food; if you want to help poor farmers, you can do your bit by buying 
Fairtrade products; or you can express a dislike of evil multinational 
companies and rampant globalisation by buying only local produce. And the 
best bit is that shopping, unlike voting, is fun; so you can do good and 
enjoy yourself at the same time.


  Sadly, it's not that easy. There are good reasons to doubt the claims 
made about three of the most popular varieties of "ethical" food: organic 
food, Fairtrade food and local food (see article). People who want to make 
the world a better place cannot do so by shifting their shopping habits: 
transforming the planet requires duller disciplines, like politics.

Organic food, which is grown without man-made pesticides and fertilisers, 
is generally assumed to be more environmentally friendly than conventional 
intensive farming, which is heavily reliant on chemical inputs. But it all 
depends what you mean by "environmentally friendly". Farming is inherently 
bad for the environment: since humans took it up around 11,000 years ago, 
the result has been deforestation on a massive scale. But following the 
"green revolution" of the 1960s greater use of chemical fertiliser has 
tripled grain yields with very little increase in the area of land under 
cultivation. Organic methods, which rely on crop rotation, manure and 
compost in place of fertiliser, are far less intensive. So producing the 
world's current agricultural output organically would require several 
times as much land as is currently cultivated. There wouldn't be much room 
left for the rainforest.

Fairtrade food is designed to raise poor farmers' incomes. It is sold at a 
higher price than ordinary food, with a subsidy passed back to the farmer. 
But prices of agricultural commodities are low because of overproduction. 
By propping up the price, the Fairtrade system encourages farmers to 
produce more of these commodities rather than diversifying into other 
crops and so depresses prices-thus achieving, for most farmers, exactly 
the opposite of what the initiative is intended to do. And since only a 
small fraction of the mark-up on Fairtrade foods actually goes to the 
farmer-most goes to the retailer-the system gives rich consumers an 
inflated impression of their largesse and makes alleviating poverty seem 
too easy.

Surely the case for local food, produced as close as possible to the 
consumer in order to minimise "food miles" and, by extension, carbon 
emissions, is clear? Surprisingly, it is not. A study of Britain's food 
system found that nearly half of food-vehicle miles (ie, miles travelled 
by vehicles carrying food) were driven by cars going to and from the 
shops. Most people live closer to a supermarket than a farmer's market, so 
more local food could mean more food-vehicle miles. Moving food around in 
big, carefully packed lorries, as supermarkets do, may in fact be the most 
efficient way to transport the stuff.

What's more, once the energy used in production as well as transport is 
taken into account, local food may turn out to be even less green. 
Producing lamb in New Zealand and shipping it to Britain uses less energy 
than producing British lamb, because farming in New Zealand is less 
energy-intensive. And the local-food movement's aims, of course, 
contradict those of the Fairtrade movement, by discouraging rich-country 
consumers from buying poor-country produce. But since the local-food 
movement looks suspiciously like old-fashioned protectionism masquerading 
as concern for the environment, helping poor countries is presumably not 
the point.

The aims of much of the ethical-food movement-to protect the environment, 
to encourage development and to redress the distortions in global 
trade-are admirable. The problems lie in the means, not the ends. No 
amount of Fairtrade coffee will eliminate poverty, and all the organic 
asparagus in the world will not save the planet. Some of the stuff sold 
under an ethical label may even leave the world in a worse state and its 
poor farmers poorer than they otherwise would be.

So what should the ethically minded consumer do? Things that are less fun 
than shopping, alas. Real change will require action by governments, in 
the form of a global carbon tax; reform of the world trade system; and the 
abolition of agricultural tariffs and subsidies, notably Europe's 
monstrous common agricultural policy, which coddles rich farmers and 
prices those in the poor world out of the European market. Proper free 
trade would be by far the best way to help poor farmers. Taxing carbon 
would price the cost of emissions into the price of goods, and retailers 
would then have an incentive to source locally if it saved energy. But 
these changes will come about only through difficult, international, 
political deals that the world's governments have so far failed to do.

The best thing about the spread of the ethical-food movement is that it 
offers grounds for hope. It sends a signal that there is an enormous 
appetite for change and widespread frustration that governments are not 
doing enough to preserve the environment, reform world trade or encourage 
development. Which suggests that, if politicians put these options on the 
political menu, people might support them. The idea of changing the world 
by voting with your trolley may be beguiling. But if consumers really want 
to make a difference, it is at the ballot box that they need to vote.