Mr Mapib meets Rhodri Morgan

Now that Wales and London have rebelled, Westminster too must change. But can Anthony Barnett intere

The most powerful Prime Minister this country has ever known, with a larger majority in parliament than Thatcher ever had, suffers his first clear defeat. At the hands of Wales. How can this be? He boldly creates a London mayor to be a showcase for his new politics, says privately that Ken Livingstone will get the job "over my dead body" but, as the NS goes to press, waits nervously for the results of Labour's electoral college. A Scottish Parliament is created on the lines he and Gordon Brown agree, run by the coalition of Scottish Labour and Lib-Dems they approved of, led by the man they backed. Yet it shows them up by producing an alternative approach to student fees.

What does all this mean? I have been asked to explain in terms that the man in a pub in Barnsley will understand. I can't refuse because I was one of those who helped to start Charter 88, and so among the first to call for what is going on in Scotland and Wales. I even did my bit to persuade Tony Blair that this was the modern way and have since been accused of "fucking up Britain".

But the man in a pub in barnsley - Mr Mapib for short - isn't interested in the constitution, is he? All he wants is a cheaper pint and the confidence that he will not have to lie in a hospital trolley for 48 hours, should he shatter his thick skull as he stumbles out at closing time. His education, his newspapers, his culture, have deprived him of the vocabulary needed to understand what is happening, while drinking beer after work has deprived his synapses of their capacity to reflect upon the situation of his country.

I reject such assumptions. Ask Mr Mapib about the euro. He won't give up his pound for a load of greasy euros. He won't be bossed around by Brussels. "You can call a pint a litre until you are blue in the face, you will not pull one out of me." And so on.

Yet it is doubtful that Mr Mapib showed any previous interest in who printed his money; he has no special attachment to the Bank of England. What explains his new concern? You can call it nationalism, but he was always patriotic. You can say it is a response to the lack of democracy, but he never regarded UK governments as very democratic. The answer is to look at the combination, at the mix. In other countries, when nationalism and democracy came together, you got, for example, national liberation movements. Illiterate people would often die for a country whose independence would be enshrined in a constitution they could not read.

Mr Mapib can read, but he doesn't have a constitution. He shares this lack with all his fellow inhabitants of Britain. He used to have an unwritten one, symbolised by Queen and Parliament and a world role. Now the monarchy is in free fall, the House of Commons is pathetic, minorities demand their rights, Rolls-Royce is German, our tap water is French, an Australian controls our satellite television, and so on. The whole thing is falling apart. European money is the last straw. With all the foreign take-overs, the only thing we have got left that is ours, and belongs to all classes in Britain, is our pound.

In the absence of a normal constitution, Mr Mapib falls back on a symbol. He talks about the constitution in the only way he can. Those who say he doesn't care about anything except his pocket are wrong. He wants his say over who mints and prints the coins and notes and who controls the interest rates. Such matters could not be more constitutional. But then the constitution never has been an abstract thing. It's about how we are ruled.

So Mr Mapib is neither stupid nor uninterested. He is more concerned about the health service than about the constitution, but so am I, since my mother has just broken her arm. So after we have shared anecdotes about the crisis in the NHS, this is what I say to him.

Point one. This country used to be well governed, compared to others. We're talking about the 19th century when the institutions that like to pretend they date back to the Middle Ages really came into existence: about the Civil Service, the law courts, even parliament; about the period when men first got the vote. The rules were not written down as they were in America but people knew how to behave; when one group lost an election they did not call in the army to overthrow the result. The trick was that parliament was the only sovereign power. It could do what it pleased. No courts, or king, nor any other country could dictate what the British parliament decided.

Point two. This was a clever system of government because it (usually) knew how to change, how to make gradual improvements. It fought wars, it extended the vote, it created a welfare state. After 1945, for example, it gave people rights to health and pensions in a way unimaginable a century before.

Point three. The changes of the recent past presented new challenges. International companies bought each other up. We had to join Europe. As the British state became less and less important abroad, it began doing more and more things at home. As a result government got worse and worse: the poll tax, pensions mis- selling, the Child Support Agency, to give just a few examples, about all of which parliament was warned in advance. Parliament had all power and it went all thumbs.

Point four. Resistance started to grow. Scots said: "Give us our own parliament, it can't make things worse" - especially after the poll tax was imposed on them early as an experiment. People started to demand rights. Others said we should become "citizens not subjects". (At this point, Mr Mapib, who reads the Sun and no longer worships the monarchy, nods his head and says: "A fair point.")

Point five. Along comes Tony Blair. He wants it both ways. He promised to be a moderniser; but he wants old-fashioned central power. So he and his advisers convince themselves that the new parliaments in Scotland and Wales are the same kind of gradual improvements the British state was always good at. At one point, Blair compared the Scottish parliament to a parish council. Reformers like me disagreed. We applauded the decision to decentralise but we argued that this was a different kind of improvement. If it was to work, it demanded a different kind of state. Decentralisation needs a new sort of centre. Whitehall has to stop being imperial and become constitutional, meaning it has to obey the same rules as everyone else. Parliament must stop pretending it can boss everyone else around. Instead, we have to become a country where everyone has rights. This is what citizenship is about.

Point six. The reformers lose the argument with Blair. He says that we don't need a new constitution; the old one will do nicely once he has tarted it up.

Point seven. Blair turns out to be wrong. What is happening in Wales and Scotland and London proves that the reformers were right. Devolution is taking on a life of its own. Meanwhile, the old centre is moribund. Just read the Wakeham Report on the House of Lords. Every time Scotland says "boo" it will be like kicking a corpse. So the more the devolution that Blair has introduced succeeds, the more it will prove that he and his spokesman Alastair Campbell are wrong in their view that, to quote Campbell, constitutional reform is crap. It turns out he was talking about himself.

Which leaves us here in Barnsley up Campbell's shit creek. I guess it has got to be England's turn next. Over to you, Mr Mapib.