Amol Rajan: The main obstacle to immigration is politics

An e-petition has been launched to force MPs to debate Britain's population, and so condemn the possibility of it rising to 70 million.

Since the petition has the support of Britain's right-wing, populist press, it should easily achieve the 100,000 signatures required by this new form of democracy.

What passes for a debate on immigration in this country is well rehearsed. Like all policies, that on immigration has both costs and benefits. In general, the costs are exaggerated and the benefits overlooked. The benefits include a more flexible, innovative and productive economy, and freedom of movement for migrants, which is particularly desirable for poor ones. The costs include increased pressure on public services, social tensions, and a lot of xenophobia.

But I haven't mentioned one benefit, which in my view is decisive.

In 2008, remittances from migrants in the rich world to their families was up 15 per cent on the year before, when it was already double the international aid budget of all countries. But this was much better than aid: being money sent directly to families, it put food on plates and coins in pockets, rather than having to be filtered through inefficient NGOs. In other words, migration saved and improved millions of lives, unbeknown to most in the West.

I should declare that I have a personal attachment to this benefit. My dad's parsimony with his two sons allowed him to send money back to India, where he could feed and educate my extended family. Many of my cousins who are now brilliant entrepreneurs themselves, creating jobs and driving growth, owe him as much as I do.

Naturally politicians in the West don't expect to get elected on their work for poor people in far away lands. When David Cameron made his stupid, immature, myopic, opportunistic and unrealisable pledge to reduce immigration from hundreds of thousands to tens of thousands, he was playing to a domestic gallery.

But it is curious to me that, conceived as a moral whole, the case for immigration is simple and convincing. The problems arise from the need for people to be elected. In other words, there is a difference between how some public servants ought to act, and how they actually do. That difference is politics.

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