THERE are millions of miserable people in the world who would like to move to the UK for a better life. It is physically impossible for us to take them all. So we must have some mechanism for controlling immigration. So said the leading Conservative thinker Oliver Letwin this week.

The man who was one of David Cameron’s policy gurus is no longer at the centre of power. But, with those words, he succinctly summarised the stance of the new Prime Minister, who this week spoke at the United Nations on the global migration crisis. There she stuck to her well-worn corollaries of the Letwin doctrine. Refugees should claim asylum in the first safe country they reach. Economic migrants should be treated less favourably than those “genuinely” fleeing war. And Britain will take no more refugees.

It is easy to understand the political pressures at work behind this. Populist insularity is on the rise everywhere. Even Europe’s most towering politician, the German Chancellor, Dr Angela Merkel — who last year gave an extraordinary lead by declaring that Ger­many would welcome a million migrants — was this week forced to row back. After her party suf­fered a humiliating defeat in the regional election in Berlin, Dr Merkel declared that, although she had no regrets over the substance of what she had done, she would have liked to turn back the clock several years, the better to prepare her people for the impact of her great humanit­arian gesture.

There was a fascinating edition of Ernie Rea’s Radio 4 series Beyond Belief this week. It looked behind the scenes at decades of the Northern Ireland peace process. Progress had been made, it revealed, not through the bland broad-brush state­ments of the institutional Churches, but through the actions of maverick priests and min­isters, who allowed themselves to be bundled into vans with hoods over their heads. They went to meet men of violence whose mind-sets were eventually changed.

There is a lesson in this for the refugee crisis. Christians need to get into the detail of this deb­ate. We might question the received wisdom of the distinction between a refugee (good) and an economic migrant (bad). Such a precise defini­tion can be inhumane. Some economic migrants are more in need of our help than others — un­­accompanied children, for example. The division needs to be unpacked, and subjected to detailed moral scrutiny.

Questions should be raised about the principle that refugees must apply for asylum in the first country where they land. On what ethical basis is choice denied to refugees? The languages they speak, the qualifications they hold, the places in which their relatives live — all these legitimately affect the destinations that they seek. And is it ethical to expect front-line countries such as Greece, Italy, or Turkey to carry a disproportion­ate burden?

Then there is the question of forced deporta­tions from the UK of failed asylum-seekers. Is it decent to deport asylum-seekers’ children who have been born in this country, or grown up here, and “return” them to a land of which they have no memory? There is much more. The devil, they say, is in the detail. But sometimes God may be found there, too.

Paul Vallely is Visiting Professor in Public Ethics at the University of Chester