A structural weakness in the Government’s policy of reducing net immigration to the “tens of thousands” was that in a free society one can control inflows but not outflows.  When the economy slows, the latter may outpace the former.  But when it grows, the reverse may be the case, as migrants enter in search of work.

This is what happened between 2010 and 2015.  At first, recession continued and net migration fell.  Then growth returned, and it rose again.  None the less, as recently as early last year, it was lower than when the Coalition took office among non-EU migrants.  It was freedom of movement that blew the door off the Conservative pledge to hit that tens of thousands target.  David Cameron and Theresa May duly downgraded that promise to an “aspiration” in last year’s Conservative Manifesto.

This is not to say that a target would be impossible to hit were EU migration to continue as now post-Brexit.  But to clamp down further on non-EU migration while leaving EU migration unchecked would distort Britain’s economic needs: as we wrote last summer, “no-one designing a rational migration system would begin by making it easier, say, for low-skill Slovenians to enter Britain than higher-skill Indians”.  It would also spit in the face of many of the voters who plumped for Brexit last month.  According to Lord Ashcroft’s research, controlling EU immigration was second from top of their reasons for doing so.

Our new Prime Minister recognises that Brexit must mean more control over EU migration – and lower numbers.  She told senior MPs during the leadership contest that, in the trade-off between staying in the single market and reducing net EU immigration, she will plump for the latter.  She has a political reason for doing so that is different from, though linked to, giving voters the reduction that they want – namely, that she failed to do so as Home Secretary, has pinned the blame on rising levels of EU migration, and knows that she must now deliver if she is to convince the electorate that her new Government means less spin and more delivery.

The problem she is running up against is that some of her most senior colleagues seem to have no faith in the net immigration reduction policy.  This morning’s Daily Telegraph quotes Amber Rudd and Boris Johnson as suggesting “that Theresa May’s new administration will no longer set explicit targets for reducing the number of foreigners coming to the UK”.  This may be because their instincts are liberal on migration: the Foreign Secretary certainly has a history that suggests this is so: he recently repeated his call for an ammesty for illegal immigrants.  Or it may be because they have been ground down by the failure of the policy to work so far.

Johnson is reported as saying that “one doesn’t want to be in a position where you are disappointing people again”, which supports this latter view.  Meanwhile, Downing Street is saying that “the Prime Minister does see sustainable levels as down to the tens of thousands”, but reportedly refuses to commit to a target.  All this uncertainty looks like teething problems as the new administration settles down.  But Ministers may not have fully grasped that with Brexit will come greater flexibility to reduce migration – and a consequent opportunity to re-upgrade the “ambition” of achieving a net reduction back into that original Conservative pledge.

They would do better still, as this site has argued, to revisit the policy altogether – and the start of a new administration provides a timely opportunity to do so.  We return to where we started.  Any policy that is partly reliant on an outflow one cannot control is a vulnerable policy.  A gross target for all migration from all sources would plainly be more desirable.  We acknowledge that some experts don’t like the idea – see Lord Green’s piece on this site in response to Bright Blue’s call for such a target in relation to non-EU migration.

His objection was that the group’s proposal would exclude students, but it is possible to frame a gross target in such a way as to include them.  But in any event, May knows well that just as “Brexit means Brexit,” it also means “Brexit means lower immigration”.  She visits Angela Merkel today.  But, on return, she must sort the confusion out.