London Briefing: Readers of the London-based Financial Times were surprised to open a recent edition to find Bertie Ahern extolling the virtues of the Common Agricultural Policy (Cap).

British readers of the FT were not surprised to find an EU leader putting his name to an article that could easily have been written by a farmer - we are used to that - but we wonder why these people bother. If there is one thing that unites this country, it is our absolute detestation of the Cap.

Ahern's article must have something to do with our current presidency of the EU and the avowed intention of Tony Blair to reform everything in general and the Cap in particular - although the chances of achieving anything during the British presidency are receding, thanks to Europe's political logjam, particularly in Germany, France and Italy.

The Cap fails all of the tests that we could set it. Most importantly, if it didn't exist, would it be invented?

Originally conceived as a deal between Germany and France to open up France to German manufactured products while protecting French agriculture, its economic and moral basis has been nil since its inception.

Ahern cites the original 1957 Treaty of Rome in his plea for no further Cap reform and argues that we should be concerned with "security" of food supply.

I don't know too many people concerned that an OPEC-style food cartel would arbitrarily cut off our food purchases - quite the reverse actually. But if we want to be paranoid why stop at food? Why not subsidise pharmaceuticals? Or any other "essential" good? Food security was a realistic concern in the immediate aftermath of the second World War. It is hardly relevant today. Next, Ahern says that it would be wrong to revisit the 2002 reforms: farmers need "stability". Well, so do we all, but things change, as textile workers and coal miners can testify. And that 2002 deal was a classic, bad EU compromise.

We would be wrong, says Bertie, to give up our subsidies ahead of World Trade Organisation (WTO) negotiations. Everybody else subsidises farmers and we can only persuade others to stop if we are in a strong negotiating position. This argument implicitly admits that farm subsidies are wrong, of course.

It is the same argument used by countries that want to hang on to their nuclear weapons.

According to Ahern, our farmers face unfair competition from abroad because all our farms are too small and cannot get the scale economies available to others. Absolutely.

But such thoughts apply to many different industries. The fact that European agriculture is relatively inefficient is no reason to subsidise it. Ahern goes on to argue that worries over agricultural subsidies taking up a massive proportion of the EU budget are also misplaced: he seems to believe that the EU budget should be massively expanded so that agriculture share falls as a matter of arithmetic.

Ahern tries to deal with the morality of the Cap by pointing out that the EU already imports a lot of food from the Third World. Again, it's true, but the argument fails the "so what?" test. Imagine how many more Third World farmers would be in business if it didn't exist.

According to the respected charity Oxfam, European citizens are supporting the dairy industry to the tune of more than $2 (€1.66) per cow per day. Half the world's people live on less than this amount. The Cap, according to Oxfam, "destroys people's livelihoods in some of the world's poorest countries".

Ahern focuses on what he sees as the benefits of the Cap. Of course, farmers are the ones who gain and the farming lobby punches well above its weight in countries like Ireland and France. But consumers vote too, especially in "rip-off Ireland", and the costs of the Cap are not just felt in the Third World.

Domestic European food prices are far higher than they would otherwise be. Typical estimates put the average food basket 25 per cent more costly than it needs to be, but I have seen far higher numbers.

Farmers are not so powerful in the UK and when we see very rich farmers - members of the royal family for instance - benefiting from subsidies, our doubts are merely reinforced.

Ahern will have convinced no one; indeed, he is likely to have reinforced our profound cynicism about the motives of European leaders.

Chris Johns is an investment strategist with Collins Stewart. All opinions are personal.