The parliamentary process is fundamental in another, even more important sense. It is a mechanism for accommodating opposing opinions and interests in our society. To gain power, political parties have to appeal to a wider base than tribal faithfuls and single-issue fanatics.
A legislature whose membership reflects the balance of political parties is therefore a natural forum for compromise. In a Brexit context this might mean membership of the customs union or the European Economic Area or something similar under a different name. These half-way houses are in many ways impure and unsatisfactory. Few people would make them their first choice. But it is probable that a larger proportion of the electorate could live with them than with any other solution.
Appeals to the referendum as an alternative source of legitimacy are really calls to reject compromise. Proroguing parliament was a method of circumventing the political process, and avoiding the pressure to compromise that is inherent in it. It is absurd to criticise the House of Commons for being just as divided as those whom it represents; and dangerous to obstruct its attempts, however laborious and accident-prone, to accommodate our divisions and avoid the aggressive extremes at either end of the Brexit spectrum.
The British constitution famously consists of many things that are not law but political conventions. Some of them are rules of practice. Others are attitudes of mind, part of a shared political culture that is based on respect for the centrality of the House of Commons. Political conventions are a better, more flexible and more democratic alternative to law. But if we are to avoid a wholly legal constitution, we must honour them.
The present government has taken an axe to convention. It has sought to use the awesome prerogative powers of the Crown, but without the accountability to parliament that alone makes the existence of those powers tolerable. It has been determined to disregard our only collective political forum. This is something entirely new in British politics.
The natural result of constitutional vandalism on this scale is that conventions have hardened into law. That is the effect of the Supreme Court’s decision. It is infinitely regrettable that it should have come to this, but better than leaving a void governed by neither convention nor law, in which the government can do whatever it likes.
The moral is that under our constitution 52 per cent cannot expect to carry off 100 per cent of the spoils. They have to engage with the rest. That is what parliament is for.