On June 1 1955, six men representing six European countries sat around a table in the poor Sicilian town of Messina. For two days they discussed plans for European integration.

Legend has it that at one point the British civil servant Russell Bretherton, sent by his country as an observer, stood up and said: “The future treaty which you are discussing has no chance of being agreed; if it was agreed, it would have no chance of being ratified; and if it were ratified, it would have no chance of being applied. And if it was applied, it would be totally unacceptable to Britain.” The talks would lead to the Treaty of Rome and the creation of the European Economic Community, the father of the European Union.

Towards the end of that summer of 1955, on the afternoon of September 4, the next step to European unity was taken: Sporting Lisbon drew 3-3 with Partizan Belgrade in the first match in football’s European Cup, the father of today’s Champions League.

At first glance the biggest football matches look like a disaster for Europe. Only during a World Cup or a European Championship do millions of Europeans paint their faces in national colours and run drunk down the street waving national flags. Holland-Germany matches, for instance, have led to skirmishes in border towns – the closest the EU gets to war.

Nonetheless, international football and Europe are like middle-aged twins. Over the last 50 years they have grown up together. A recent exhibition at the Musée du Cinquantenaire in Brussels - ‘Only a Game?’ -traced this shared history. Almost unnoticed, top-level football has helped build Euro-patriotism. All that European leaders need to do is sit back and keep their hands off it.

Today the main motor for creating a sense of belonging in European countries is sport, particularly football. The most watched television programmes in most EU countries are matches featuring the national football team. These are evenings of nationalism. But football also encourages regionalism (Newcastle United as the club of England’s northeast region) and even village patriotism (the hard-fought derbies at the lowest levels of amateur football).

All that is lacking is a football team representing Europe. Some in Brussels have tried. In 1982 the Adonnino committee, led by the Italian MEP Pietro Adonnino, proposed measures for creating European sentiment: a Eurolottery, the blue flag with the gold stars, and European sports teams. Today only one such team exists: every other year Europe plays the US in golf’s Ryder Cup. But even that is essentially a British-Irish team with a couple of “token continentals” thrown in.

Nobody outside Brussels has shown any desire for EU teams in other sports. Nonetheless, 20 years after Adonnino, another Italian tried again: in 2004 Romano Prodi, then president of the European Commission, proposed sending a united EU team to the next Olympics in Beijing. His spokesman pointed out that if such a team had competed at the Athens Games, it would have won nearly three times as many medals as the top country in the medals’ table, the US. But Prodi’s suggestion was laughed out of the room. In a Eurobarometer survey for the Commission, only five percent of Europeans said a European Olympic team would make them feel more like “European citizens”. Sports fans only want national, city and village teams.

And yet football does create Euro-patriotism – not through European teams, but through European competitions. Two of the three main international football tournaments – the Champions League and the European Championship – date from the first years of European integration. Both are premised on the existence of Europe. Both have grown into pan-European festivals, in which different nationalities sometimes support different teams, but all live by the same rules, have the same café or pub conversations, and feel part of Europe. Meanwhile older non-European football tournaments – like the Home Nations tournament between the British nations, and the Mitteleuropa Cup – have faded away.

Most football in Europe is played by clubs in their national leagues. However, even this domestic football makes Euro-propaganda, because the Babel of nationalities who play for the best clubs are mostly exemplary European citizens.

Thirty years ago this exchange of labour barely existed. Borders were still closed to foreigners, and only the very best players ever moved abroad. But gradually EU law – particularly the Bosman ruling of 1995 – has dissolved Europe’s footballing frontiers. In England today, Arsenal has a French manager, Liverpool a Spaniard, and Tottenham, for now, the Dutchman Martin Jol. Until José Mourinho’s sudden departure from Chelsea, there were more foreign managers in the English top division than at any time between 1900 and 1995. More than half the Premier League’s players are foreigners, most of them European citizens.

Hardly any other business sector in the EU employs such a mix of Europeans. Only about 2 percent of all EU citizens live in another EU country, because few companies recruit bus drivers or office staff from neighbouring states. Football is possibly the EU’s most integrated industry. It is the common market on legs.

For many football fans, great players are the only people from other EU countries whom they “know” personally. Europeans do travel a lot, but the contacts they make tend to be superficial: with waiters, shopkeepers, or strangers in nightclubs. Thanks to football, the common man – and increasingly, the common woman – has a clear image of some living people from elsewhere in Europe. Twenty years ago, how many Britons could name a living Frenchman or German? Perhaps Brigitte Bardot and Helmut Kohl. Few European film stars or musicians cross borders (think of the French rock phenomenon Johnny Hallyday).

But since 1995 European footballers have been among the best-known people in Britain. At one point the Premier League could simultaneously boast Eric Cantona (French, handsome, charismatic, brilliant footballer, arrogant), David Ginola (French, handsome, charismatic, brilliant footballer, arrogant, enemy of Cantona), Ruud Gullit (Dutch, handsome, charismatic, etc.) and Dennis Bergkamp (Dutch, charisma-free).

If the European Commission had a marketing department, it could not have designed better faces of Europe. These footballers personified what for most Britons had hitherto been abstractions: “the French” and “the Dutch”. These men tended to be better footballers than the natives, sometimes spoke better English, and seemed to be more intelligent. Ginola and Gullit were each voted Britain’s best-dressed man.

In tribute, British fans often adopted foreign symbols. United fans had a song for Cantona based on the Marseillaise. Arsenal fans briefly sang 'Allez les rouges' for their Frenchmen, and when the German striker Uwe Rösler became a cult hero at Manchester City, the fans wore T-shirts saying: “Uwe’s Grandad bombed Old Trafford”, commemorating the Luftwaffe’s strike on United’s ground.

This adoration of foreigners was repeated across Europe. The Portuguese Pedro Pauleta was long the most popular footballer in Paris; the moustachioed Hungarian Jozsef Kiprich became a cult hero in Rotterdam.

Many footballers settle in their adopted countries after their careers and these football expats are living advertising posters for the European ideal of free movement of labour. They do interesting, well-paid work in other EU countries, without apparently suffering much from homesickness or anything else.

Football, then, encourages dual emotions: nationalism, but also an almost unnoticed Euro-patriotism. Of course nationalism is the stronger feeling. Nobody ever ran drunk down the street waving the EU flag. By contrast, one of the greatest Dutch popular festivals occurred on the Tuesday evening of June 21, 1988, when millions celebrated on the streets after Holland beat West Germany 2-1 in Hamburg.

But in recent years Europe’s football nationalism has lightened up, becoming a sort of “party nationalism”. For decades football nationalism was focused chiefly against Germany. England, France, Holland and others all considered the Germans their main rivals. Of course this had to do with the war. For the French, their greatest football trauma was defeat by the Germans in Seville in the 1982 World Cup. The French TV commentator Georges de Caunes says that for French males of his generation, the karate kick inflicted that evening by the German keeper Toni Schumacher on the Frenchman Patrick Battiston evoked wartime feelings.

However, the last two major tournaments have shown that that hatred is weakening. As the war fades from the collective memory, so does antipathy to Germany. At the European Championship of 2004, when Holland and Germany met again in Porto, their fans sat mixed in the stands. Not only did they not fight; they didn’t even provoke each other. “A step forward in history,” a security official at UEFA, the European football authority, told me later.

The last World Cup was a Europe-wide lovefest for the German hosts. The fans still supported their own countries, but celebrated on the streets together aided by beer. Oliver Bierhoff, the German team’s general manager, noted that supporters had become less concerned with results. Football nationalism is cheerier now.

Admittedly the old rivalries still exist. In a recent survey by the British company Tickbox.net, most England fans named Germany as the team they most enjoy beating. However, that no longer had much to do with the war: the most fervent fans were young, while the ones least preoccupied with Germany were the over-55s.

The new party nationalism often coexists with Euro-patriotism. In a Eurobarometer poll in 2005, 63 percent of Europeans claimed to be “very proud” or “fairly proud” of being European. But almost all of them were proud of their own countries too. Euro-patriotism doesn’t replace nationalism; it accompanies it.

Euro-patriotism is widespread but rather weak. In that same poll, only 12 percent said they were “very proud” of being European; the rest were only “fairly proud”. So Brussels mustn’t imagine that millions will ever throng the streets for a European team. Football tournaments will remain draped in national colours.

Nonetheless, Brussels can be “quite proud”: firstly, because the EU is the world’s best football region, and secondly because all those national flags and painted cheeks are the last, toothless manifestations of old European nationalism. Partly thanks to football, the EU has won.