By Paul Goodman
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Migration Watch's immigration e-petition calling on the Government to "stabilise our population as close to the present level as possible" is gathering signatures at a rate of a thousand an hour, backed by the Sun, the Daily Mail and (in our more modest way) ConservativeHome.  As the organisation points out, "net migration from the whole of the EU has made up about 29% of the total" – not an insignificant slice of it.  The net inflow of some 30,000 people a year over the last five years has taken place within the framework of our EU obligations.

Migration Watch points out that "even if the UK adopted a firm policy of opting-out of all new EU legislation on asylum and immigration matters, there are still other ways in which the provisions of the Lisbon Treaty could affect the UK’s policy in these areas": it refers particularly to the role of the European Court of Justice.  The role of the court is a very live issue.  For example, the legality of the third of Nick Boles's four proposals to control immigration – requiring migrants from within the EU to leave Britain if they don't have a job or can't support themselves – is disputed.

All in all, immigration from the EU has brought some benefits and many problems.  As ever, the flow of arrivals hasn't been spread evenly but concentrated in particular places, leading to pressure on housing, schools, hospitals, transport and social services.  There is a link between popular support for immigration control and the live debate about the repatriation of EU powers.  Roughly three quarters of those polled want immigration to be reduced and the issue is "highly salient" (unlike the EU issue as a whole): about half of Britain's ethnic minorities support a cut.

How far should the Conservatives go on the repatriation of powers?  How hard should the party be pressing David Cameron?  Each of us must decide for ourselves, but my answer is: not so hard as to make the Government inoperable or bring it down – thus forcing an election which, on the present constituency boundaries, risks a Labour majority or, more likely, another hung Parliament (in which a small gain of seats by the Opposition would provide the numbers for a Labour-Liberal Democrat coalition with Ed Miliband as Prime Minister).

But it would be wrong to let the best be the enemy of the good: in other words, to hold that since the negotiation of a Swiss or Norweigan free trade package is unlikely under this Government, there's therefore no point in pushing for any at all.  What, therefore, should be at the front of the queue?  Again, each of us must answer for ourselves, and one popular answer among Conservative MPs seems to be: social and employment laws.  Expect the Fresh Start Group, perhaps the 81 Group, and others to produce proposals shortly.

There are two reasons for this, one of which reaches back to the past, the other of which is very much in the present.  John Major gained an opt-out from the Social Chapter under Maastricht, and Tony Blair did away with it: the party tends therefore to agree about reviving such an opt-out while others remain more contentious.  And having more freedom of manoevre over social and employment laws would be a boost to growth at a time when it is urgently needed.  No wonder that in Tory terms the idea is uncontentious.

But this isn't so elsewhere.  Labour's response to an attempt to regain control over our own employment laws would be: "The Tories want to put your job at risk" – potentially a powerful appeal at a time when growth is scanty and the economic outlook bleak.  This helps to explain why Marc Glendenning of the People's Pledge has argued on the site that such a move would be "a strategic disaster from an anti-EU perspective because the social chapter has obviously been popular amongst those on the left".

So what could be put at the front of the queue instead?  My answer is obvious from the above.  There is emphatic support for reducing immigration across the voter spectrum.  Ed Miliband's party is increasingly divided on the issue: note the position of his adviser, Maurice Glasman and the "Blue Labour" tendency.  Controlling our borders has a broader and deeper appeal than, say, controlling our fishing: unsurprisingly, it was the top answer that came back when we polled recently about unpopular aspects of the EU.

But government can't work out what to repatriate without also working out how to repatriate. (I leave the different but related matter of the Human Rights Act and the European Convention of Human Rights for another day.)  The obstacles are formidable: above all, the role of the ECJ.  Andrew Lilico will be writing more about this matter tomorrow, but it's clear that as well as heading the queue of powers to repatriate with subjects that have wide appeal, we need proposals to do so that reach very deep.

That means the unambiguous reassertion of the supremacy of Westminster: in effect, placing Britain outside the EU legal structure in relation to any matter that is repatriated.  Bagehot of the Economist has written that Germany simply won't put up with this – that, rather than be frustrated in any new treaty negotiation, it will lead the charge to draw up a new treaty outside the EU structures. In effect, Britain could be thwarted in repatriating any powers at all, presumably including those that David Cameron committed himself to in the last Tory manifesto.

In which case, support within the party for withdrawal would rise further.  (The Government is already careering towards a further fracas over more money for the IMF.)  I've already written that in some circumstances Cameron may have to pledge an in/out referendum: in these, that timetable could be accelerated. Events would start to move very fast.