A fortnight ago, travelling back from a meeting with fellow European ministers, I felt uneasy. The Irish referendum had shaken the confidence of European leaders. Commentators and politicians were rushing to interpret the result in a way that vindicated their pre-existing positions. The debate was fracturing along familiar lines: two-speed Europe, an end to enlargement, a trading bloc not a political union.

I’ve always believed that Britain’s strength in the world needed engagement in Europe, not isolation. But I didn’t feel comfortable dismissing the negative result out of hand. After all, today only 50 per cent of Europe’s 500 million citizens think their country’s membership of the EU is a good thing, down from 75 per cent twenty years ago.

We will not get Europe right if we offer a tin ear to the people. There are obvious and justified complaints – uncertified accounts, MEPs’ expenses and the CAP. Of course, the EU, like most political institutions, can be infuriating – sometimes petty, sometimes excessively bureaucratic, slow to respond on new issues, with entrenched interests that are difficult to shift.

But there is a more fundamental issue. For my parents’ generation, haunted by the memory of economic depression, fascism and war, the European mission was clear and inspiring.

It would put people together after a terrible decade in which their leaders had torn them apart.

My generation has no memory of the founding events of the EU, still less of the terrible years that were their inspiration. My connection with that time is inherited. My mother was born in Poland, my father in Belgium. I grew up keenly aware of the imperative of politics, always and for ever the best option.

The defining events that have punctuated the lives of my generation are different. They are the fall of the Berlin Wall and 9/11.

The EU needs a new mission that reflects the hopes and fears of the next generation, and the problems that cannot be solved without international cooperation.

It used to be the case that national government was the bastion of order, the front line of the citizen’s defence against the risk of armed conflict and economic turmoil.

Protection was the preserve of the nation-state, acting as a single body politic in negotiation, or in conflict, with others.

That is no longer true. Risks have gone global. There is no national solution to the credit crunch, to oil and gas insecurity, to climate change, to terrorism. These are all questions of protection, they are all international by their very nature. Global institutions are too weak to address them, and nation-states are too small. We need the European Union.

There are three global threats which the EU needs to address. First, in the next century, we face the twin threat of climate change and energy insecurity. If we don’t take the right decisions now, in 10 years’ time, emissions will be rising, and we will be more dependent on scarce vulnerable supplies of oil and gas. The answer is for Europe to lead a low-carbon energy revolution.

Through regulation we can set standards for cars and appliances that transform technology not just within Europe but beyond. Through the EU Emissions Trading Scheme we can build a global carbon market which could transfer billions to China, India and Africa to fund clean energy.

Second, Europe has the largest single market in the world. But it is unfinished. We need to complete the single market so that it is as easy for plumbers, accountants and architects to sell their services around Europe as it is for retailers to sell goods. Instead of giving in to the forces of protectionism, Europe must push for new global trade deal.

Third, Europe’s security is threatened by instability beyond its borders, from conflict and failing states to terrorism.

That is why, in 10 years’ time, we should be able to look back at normalising the Balkans. Turkey should be inside the EU acting as a bridge to the Muslim world. We should be debating how fuller access to the European single market can act as an anchor for stability and democracy in North Africa and the Middle East just as it has in Eastern Europe. And – if we build on President Sarkozy’s recent proposals – the EU and NATO should be working much more effectively together to resolve conflict and manage crises where they occur.

These are all practical problems to which cooperation in Europe is the answer. The original purpose of the EU was historic, even poetic. Perhaps we have entered a more prosaic age, one in which Europe defines its core business and sticks to it. I believe that is the best way to help restore citizens’ confidence in the European project. If we keep our minds trained on the right issues, the case for Europe can be made. No, more than that, the case for Europe must be made.

David Miliband is UK Foreign Secretary