David Cameron's very clear victory paves the way to another period of uncertainty, at the end of which the United Kingdom and the European Union will be compelled to clarify their relations. Ideally, this period should be as brief as possible: given the many challenges – both external and domestic – that Europe has to deal with, institutional questions are the least of Europeans' worries.
So the outlines of the 'plan B' that will have to be pulled out of…