The tragedy of the Brexit Chequers summit

Today has been so bigged-up as a day of destiny for Britain that it can only deliver disappointment. Even if we do have white smoke rising from the chimneys of Chequers by the end of the day, together with a photo full of strained smiles as the Chancellor and Foreign Secretary apparently agree on a blueprint for Brexit full of delicate compromises and trade-offs, why does anyone think that Michel Barnier and his team will give the nod to what is agreed?

It is remarkable how little this matter has been raised over the last few days. We have had endless speculation on the internal politics of the cabinet. We have had rumours of resignations, a last minute summit at which David Cameron is said to have talked Boris out of a threat to resign. But scarce acknowledgement that the Cabinet is not going to get to lay down the landscape of Brexit by itself.