Arguments for and against Britain leaving the European Union have escalated in recent weeks, particularly among Conservative politicians. So why put them to a public vote at all?

Why have a referendum at all?  What makes British membership of the European Union an issue different from others that are no less significant for the constitution, security and international involvement of our country? Why not a referendum on our membership of Nato, or our maintenance of a nuclear deterrent? Why not ask the people whether they wish to continue being ruled by a hereditary monarch? Or whether England should have a parliament separate from that of the United Kingdom?

On none of these vital matters has there ever been the direct consultation that the Eurosceptics say their obsession deserves, while our signature of the Treaty of Rome has already been the subject of a referendum in 1975, which Margaret Thatcher, then Leader of the Opposition, said would settle the matter once and for all. Why on earth are we now having another?