A diplomatic spat that underlines our alienation from the heart of Europe

Rarely do diplomatic differences emerge into the public domain quite as unambiguously and undeniably as the British-French contretemps that erupted at the last European summit and now refuses to die down. At one level the argument is indeed, as Downing Street maintains and the French Agriculture Minister insisted yesterday, about the Common Agricultural Policy and its reform. At another, though, the CAP dispute is just the latest manifestation of Britain's continued discomfort with the European Union and of the eternal triangle of tension that links London, Paris and Berlin.

Few, probably even France when it squarely contemplates the future, contest the inevitability of CAP reform. The expansion of the EU will force the changes that France has long resisted. The entry of Poland, in particular, with its multiplicity of small, private farms, will alter the EU's economics forever.

France may hope that its weekend pact with Germany has fended off real change until 2013, but it has probably delayed it only until around 2007-08 – long enough for M Chirac to have left office without betraying the interests of French farmers. The edifice of the CAP may collapse before that, however, under the combined pressure of expansion and the faltering economies of the richer, industrial states.

As Prime Minister of the country which is one of the biggest net contributors to the EU budget, Tony Blair is right to be pressing for organised reform of the CAP still earlier. He is acting both out of economic realism and consideration for Britain's best interests. That is a compelling combination and one for which he deserves only praise – at home.

But when he says – as his spokesman did yesterday – "People just have to get used to the idea that just as the French will fight for their interests, so will the UK", there is an edge there, an irritation, that betrays just how far Britain remains outside the European mainstream.

Mr Blair's efforts to form alliances to pursue Britain's interests have sometimes misfired and at other times not lived up to expectations. Last autumn's ill-fated Downing Street dinner, conceived à trois and eventually held à sept, was one case in point. So was Mr Blair's last-minute endorsement of Gerhard Schröder's re-election campaign. It looked at the time like an ingenious example of short-term diplomatic opportunism. And so it has turned out: Mr Schröder dined at Downing Street two days after his election. Last week, he signed up to M Chirac's vision of CAP non-reform. Germany has national interests, too.

Mr Blair should know that the view of Britain, as seen from continental Europe, is rather different from the one Downing Street likes to present. While Mr Blair pledges to place Britain at Europe's heart, Britain is seen from Europe as half-hearted; the evidence is our dithering about the euro. From Paris or Berlin, London still appears to lie halfway across the Atlantic – more than halfway, as the global coalition against terror has transmogrified into a bilateral alliance against Iraq. Far from being isolated in his cautious approach to a war, as the British maintain, M Chirac has been voicing the misgivings of most of Europe, and Russia. If anyone is isolated on Iraq, it is Britain.

The quarrel between Britain and France is hardly the first and it will not be the last. But the open ferocity of this spat marks it out from previous disputes. If it persuades Mr Blair to see himself a little more as others, notably France and Germany, see him, it could be salutary.