True to form, the Lib Dems announced that only they have a principled position on Brexit – and promptly planted themselves firmly on the fence. Boxing clever by promising a referendum once terms are agreed, with the option to stay in the EU, may differentiate them from the big parties, but only because, dainty footwork apart, it isn’t a sensible thing to propose. First, by following the Tory line of treating a consultation as if it were legally binding, it implies a legitimacy for the first referendum which has been half the problem all along. Second, a re-run referendum would need the assent of Parliament. If Britain fails to get terms which include access to the Single Market (which grown up MPs know Britain urgently needs), why give them a get out of jail card? If they still want to leave, despite adverse terms, they’ll vote against going to the public again. On the other hand, if they were ready to vote for a second referendum, it’s hard to see why the Government shouldn’t just go ahead and get out of Article 50 as best it can. It’s not as if they haven’t got an example of the danger of chucking EU membership up in the air to see what way it’ll land!