Constitutions are not to be trifled with. Anyone who wishes to discuss constitutional questions should start with the Latin root. A constitution is something which helps us to stand together. This can take many forms. There is a common misunderstanding that a constitution must be a document, and that because Britain does not have a written constitution we do not have a constitution at all. That is nonsense. The British Constitution is like Antaeus. Its strength springs from the soil of its native land. It derives its authority from the customs and habits of the British people, whose political temperament is a volatile blend of reverent allegiance and democratic truculence. It is so rich, so complex, so steeped in history, tradition and convention, so buttressed by so many institutions, that it would be impossible to summarise on paper. Per contra, other countries have discovered that a written constitution, being on paper, is easy to tear up.

As Burke wrote: "A state without the means of change is without the means of its conservation". The same applies to constitutions. Over the centuries, the British Constitution has evolved. Like the Common Law – like Toryism – it is an unending dialectic between old principles and new circumstances. But constitutions are important. If we blunder into thoughtless innovation, we may quickly find that we are no longer standing together. If anyone believes that this is an exaggeration, let him consider all the constitutional reforms of the Blair era: Europe, the legal system, devolution. None of them were thought through. All of them have led to confusion. To be fair to Mr Blair, there is no evidence that he ever cared a fig for the unity of this country or the integrity of its Constitution. Those who do not share his destructive insouciance should shun his example.

It follows, therefore, that constitutional reform should only be undertaken with regard to Falkland's dictum: "When it is not necessary to change, it is necessary not to change". Change should be the fruit of long deliberation: hard thinking. Does anyone believe that this is true of Mr Clegg's attempt to clogg the House of Lords? Nick Clegg wanted to abolish the pound. Fortunately, he was frustrated. He then moved on to the electoral system. The voters were not having any of that. Now, his thwarted wrecking impulses have moved on to the Lords. This is not careful constitutional reform. It is petulance. The other day, Mr Clegg told us why he was in favour of an elected second chamber. He said that our current arrangements were disreputable, because in almost all other counties, members of second chambers were elected. That was such a revealing comment. Nick Clegg obviously believes that whenever Britain is different from other countries, Britain is in the wrong (oddly enough, he has stopped making that argument about our currency). But why should he take such a negative view of our institutions?

Take Europe. Over the past century, with the exception of Ireland, Sweden and Switzerland, every other nation much larger than the Vatican City has either invaded its neighbours, been invaded by its neighbours or had a coup. Although Britain's immunity from all that owes more to the English Channel than to the House of Lords, it does not suggest that our institutions are in bad shape. We have managed to combine a vigorous democracy with strong government. We enjoy the rule of law. The recent debates about extradition have drawn attention to the differences between various legal systems. I am not aware of anyone arguing that ours is inferior. Furthermore, British constitutional evolution has almost proved Our Lord wrong. You can put new wine in old bottles. Our democracy is enhanced by ancient forms, such as the Monarchy and the House of Lords.

That said, there is one respectable argument for a fundamental reform of the Lords. You should support it – if you believe in weakening the House of Commons. If you think that the Commons is too untrammelled, if you fear the brute force of a Commons majority, there is only one way to respond: a democratic counterweight. The current House of Lords can obstruct the government. It can exact concessions and require a degree of rethinking. But its blocking powers are limited, because it does not have a democratic mandate. If you think that the British system would be improved by legislative gridlock, you should support reform. But if you believe in strong government, why make a change which would undermine that? To paraphrase Lord Reith, the UK has elective dictatorship tempered by electoral assassination. Unless there is a coalition or an unreliable Parliamentary party – as after 1992 – the Prime Minister has great power. Equally, he has no excuses when his contact comes up for renewal after four or five years. So that is the real question: do you like your Prime Ministers strong or weak?

There is a further issue. Why is local government so uninspiring in this country? Because most of it was invented and imposed from the top down. There has never been strong local enthusiasm; voter turnout is always low. The same would be true of this new House of Lords. There is no public demand for it. There would be no public interest in it. You cannot trumpet a democratic reform if the demos does not give a monkey's. There is one final point. The current House of Lords works. It does a great deal to improve legislation. Its composition may be as curious as some of its Gothic architecture. But, like the architecture, it achieves harmony: a harmony of expertise and common sense, of grandeur and modernity. In a country where so many things do not work, it seems bizarre to devote virtually an entire Parliamentary session to destroying something that is successful, when the proposals for its replacement are so ill-thought out. There must be an easier way of appeasing Nick Clegg's vanity.