Whether we like it or not, we live in a world where what happens in other parts of the world has an impact on our lives. The Government’s ability to protect people from terrorism here is affected by its ability to stop people becoming terrorists elsewhere. Their ability to limit immigration here is affected by weak economies that drive migration elsewhere. The cost of food in our supermarkets depends on whether farmers elsewhere have a good or bad year.

Meanwhile across the world, governments, with the exception of a few rogue outliers, have recognised that the way to tackle shared challenges is more cooperation not less. Last year, the Chinese joined governments from across the world at the Paris climate summit, spotting an opportunity to get pollution levels down in Beijing. The US Government worked through a coalition of states to bring a nuclear Iran to the negotiating table, knowing it couldn’t do it alone. Last month, high-level delegates from seventy countries met in London, recognising only shared action would lead to better aid for the victims of the conflict in Syria.

By accident more than design, the EU got ahead of the game a long time ago. A club formed to build peace and prosperity among its own members became their most effective means for doing exactly this elsewhere in the world. And in turn, beyond the most hopeful imaginings of its founders, the club has become a leading source of power and influence globally.

Whether or not the EU is any good at international development, and whether Britain’s membership of the EU enhances its ability to do international development, is not going to sway the average undecided voter in the June referendum. But the EU’s role in international development has been an important part of its growing soft power in the world – and to date the British government and British aid organisations have only benefitted from this fact.

The EU is one of the world’s most generous aid donors. The development and humanitarian assistance provided by the EU scores highly in rankings of transparency and accountability. The fact that funding from member states is pooled allows it to go further and wider, and to be used more efficiently. The assistance provided becomes the living embodiment of proud European values across the world – stability, democracy and human dignity. Values which, while not exclusively European of course, are nurtured by Europe’s support for them.

For Britain, which delivers 10% of its development spending through the EU, membership delivers value for money. It gives us reach into countries where we have no presence of our own but vital security interests, such as parts of West Africa affected by violence and climate fragility. It enhances our ability to support countries and tackle issues where British aid alone wouldn’t make enough difference, for example the humanitarian crisis in Syria and support for those who have had to flee. In 2014, the last year for which statistics are available, the EU delivered more humanitarian assistance inside Syria than anywhere else in the world.

Beyond delivery of aid, being inside the EU amplifies Britain’s voice and influence in the world on issues from trade to climate change, from democracy to human rights. Britain earns respect within the EU for being a generous donor, giving Britain an ability to shape the work that the EU does, through its collective power, to tackle these issues in the world.

As a Labour movement, fairness and equality are in our DNA, and we should embrace any opportunity to advance these values at home and abroad. The EU gives us the opportunity to do precisely this, as a champion of international development and an institution better at doing it than most. Leaving the EU would likely reduce both the impact of our aid and our ability to make a difference to the lives of the world’s poorest people, be it through fairer trade or tackling climate change, the effects of which are most often felt by the poor.

But it’s not just about international development. Leaving the EU makes it harder to influence all the global debates and decisions that affect us. Cooperation is tough, and often the EU gives us a head start. Think again of the cooperation that was required to secure a deal on Iran’s nuclear programme, or the cooperation that will be required to end the conflict in Syria – first and foremost a tragedy for the Syrian people, but not without implications for Britain.

And that’s the bottom line: Even if undecided voters don’t care about our values, and don’t see EU membership as a route to advancing them, self-interest should kick in. Being part of the EU boosts Britain’s standing as a global power, and gives the British Government more power to affect global decisions and actions that directly impact the everyday lives of British people.

Laura Kyrke-Smith is Chair of the Labour Campaign for International Development. She Tweets @laurakyrkesmith

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