Britain is currently balls-deep in "a once in a generation summer" of "gentle patriotism," according to Labour leader Ed Miliband, with a boss-eyed public munching its way through a series of flag-waving exercises birthed last year by a royal wedding, fattened by the Diamond Jubilee, shipped off to the abattoir by Euro 2012 and unceremoniously slaughtered by the Olympics. All we need now is another lovely war and we'll be gorging on the entire nationalistic herd.

My peers indulge in this nonsense like bullying seagulls pecking each other for chips thrown on the prom, blindly tearing at whatever artery-plugging junk they're fed by people bigger than they. What really galls me is that so many people excuse it as "a bit of harmless fun". Why fear the Jubilee? It's just a few days off with a "cheeky" lager and a calorie overdose. Why not celebrate our nation?

The biggest problem with patriotism is that it enforces a sense of national identity, that it is, literally, nationalistic. As we move forward into the 21st Century, the problems we face are global, and this "convenient fiction," as Joyce had it, hinders our ability to unite on a planetary level by dividing us and encouraging us to think - and act - on a local one. In a time where national identity should be being resigned to the foreign country of the past, patriotism promotes it. Want the coming generations to face a nightmarish environmental scenario? Keep up your steady diet of pride.

When we group under a flag we define ourselves in opposition to others; we display intention to win rather than solve. The ecosystems on which we depend are collapsing, in case you hadn't heard, but time and again international committees fail to reach accord on climate change, deforestation, over-fishing and the like because the nations involved are duty bound to represent the commercial interests of their people. Their people; not people. David Cameron couldn't even be bothered to turn up to Rio+20.

Nationalism has failed in a real sense, and unless we seize the vision to move beyond it global society may very well fail with it. As a concept it cannot fulfil global environmental needs or those of worldwide trade systems: we need a global system, not a national one. We're seeing the nationalistic end-game, as the dinosaurs of conservatism attempt to convince the public that the way forward is backwards. If the euro is experiencing problems, France must revert to the franc. If the euro-area shudders, Britain may consider an exit. National interest must precede the interest of humanity, we're told.

Of course, patriotism suits our rulers very well. It keeps them in power. Tough economic times allow the establishment to offer nationalism as a comfort food, an overdose of bird-baiting stodge to lure us away from the the fitness regime we hope will eventually prevent a middle-aged heart attack. Haven't got enough money? Wave this. Happy now? Good. "We're all in this together".

But patriotism, now matter how "gentle," nooses our necks and pulls us, blindfolded, to the right. When we allow our leaders to capitalise on nationalism, instead of supporting those who demand greater unity, we invite extremism back into mainstream politics by saying we want to be bound by our physical borders and those that would further close them. By painting a Union Jack on your face, by indulging in displays of national pride, you're perpetuating the stench of UKIP, the droning fart in Europe's political spacesuit, and offering a bunk-up to fun-loving racists like Nick Griffin and Marine Le Pen. You're allowing Theresa May to ruin people's lives. You're showing presidents that they must push to the extreme right in their search for popularity.

You do this by saying you believe in the flag.

While you cheer "the boys" on the TV, dressed in your England shirts, you're supporting a system of politics that will eventually destroy our ecology. While you prise grease-sodden sausage rolls away from your Union Jack paper plates and swill beer in honour of the Queen, you allow fascism to, yet again, root in the paving stone cracks of Europe's national borders. By being patriotic, by feeling pride in "your" flag, you are encouraging racism and pushing life as we know it towards further crisis.

God save the Queen. Just a harmless bit of fun. At least try to think about it the next time you go to string up the bunting.

Follow Patrick Garratt on Twitter: www.twitter.com/patlike