The government should say that Britain is leaving the EU because it wants no part of the EU's supranational ambitions. The relationship Britain ought to propose is one between law-making governments -- the U.K. on one side and the EU and its member states on the other -- not one between law-taking subsidiary units of a single constitutional entity. Subject to that, Britain will seek the maximum amount of economic integration and diplomatic cooperation.
Broadly stated as those goals may be, they're clarifying. For instance, they rule out the so-called Norway option, which grants access to the EU's single market but also requires free movement of workers and automatic application of EU legislation. They also rule out arrangements that would forbid Britain to negotiate free-trade agreements with other countries -- so no customs union (with a common external tariff), like the one the EU has with Turkey.
For many Brexit voters, control of immigration was the sticking-point, prompting the question: Could access to the single market be separated from free movement? It depends what you mean by "access to the single market," a term that's used too loosely. In EU-speak, the "single market" is much more than an economic arrangement: It's an explicitly supranational undertaking, bound up with free movement of people as well as with free trade in goods, services and capital -- all understood as indivisible constitutional principles.
By definition, an intergovernmental relationship therefore rules out membership of the single market. But it doesn't rule out access. Free trade in goods, services and capital, and a high degree of labor mobility, are all possible, so long as those things are understood not as the constitutional underpinnings of a supranational order but as the terms of an ambitious free-trade agreement. And that, in a nutshell, is what Britain should aim for in its future relations with the EU -- an enhanced FTA. A new paper by Jean Pisani-Ferry and colleagues for Bruegel, a European think tank, says more about how this might look.
Britain's current full compliance with EU rules means that, in economic terms, the straight-line distance from here to there is not that great. In legislative terms, though, the journey is a long haul: EU laws have to be recast as British laws, and the reciprocal obligations of the EU and its members need to be recast accordingly. New agreements with the World Trade Organization and non-EU countries will also be needed. Then allow for the detours demanded by Article 50, and the punitive instincts that an exasperated EU might indulge, and the actual distance between here and there is likely to be exhausting. That will be the price of Brexit. In the end, though, and inconceivable as it may seem to respectable opinion in Britain, the destination -- restoring the U.K. as a sovereign law-making nation, with a government accountable to its citizens -- might be worth it.