London may be the centre of the universe, but that is no longer any reason for the British government to ignore the provinces and our other major cities.

Thus far, recognition of this important fact has come mostly from London envy and the desire to drag the capital city down a peg or two – not a very sensible policy as far as the national interest is concerned. But the debate is gradually coming to be seen in terms of helping the UK’s other cities to grow and to prosper. In essence, the debate is moving away from a Labour-style “let’s drag everyone down to the same mediocre parity” argument and towards a “let’s create opportunities for innovation and growth and see what happens” proposal. This is most welcome.

The economist Jim O’Neill, writing in The Telegraph, has half of a good idea when he proposes merging northern cities and devolving fiscal powers to them in order to spur economic growth:

After considerable discussion, and for primarily practical reasons, we settled on what we are describing as the 15 largest “metro regions”. This is not to downplay the importance of other cities, towns or villages, but to emphasise – as many experts have concluded – that it is the largest urban areas that usually generate the most economic activity. We need to concentrate our efforts there; evidence from other countries shows that the biggest urban areas matter most when it comes to unleashing a step-change in national economic activity.

In this context, I raised a delicate topic with the last of three panels: namely whether the Greater Manchester area is, in fact, big enough. If you look at a list of the world’s largest cities by population size, you have to go a long way down from London before any other UK city appears. Some argue that in the absence of another city with anything like the population and diversity of London then attempts to boost growth, however smart, won’t lead to much.

This is good stuff. Greater Manchester is certainly prime for devolution of fiscal powers under a unitary authority and an elected mayor, along the lines of London. Manchester is a large, globally recognised city. Granting it more power to alter local taxes, services and policies would be a great example of localism at work.

This blog has long advocated wholesale constitutional reform for the United Kingdom, in which England would gain its own Assembly to debate matters relating to England only, and powers of taxation and policymaking would be equalised between the assemblies of the four home nations under the UK Parliament.

Basing this new English assembly in one of the great northern cities would be a boon to the host city and would help to reduce the London-centricity of political and media focus in the UK without taking anything away from London, which remains the goose that lays the golden egg.

Unfortunately, after proposing the devolution of powers to major cities, O’Neill follows a somewhat different train of thought and his economist brain takes charge to the detriment of what was otherwise an intriguing proposal:

In the spirit of trying to keep an open mind, I quizzed the group further. What did they think of the notion of “ManPool”, where Liverpool and Manchester might bring together their populations and resources to create a “supercity” in the north? Many Telegraph readers might be familiar with the depth of history between Liverpool and Manchester, even if they are not followers of a team from either city. Football allegiances aside, the reaction I received made it pretty clear the prospect was highly unlikely from an administrative perspective.

Sometimes, things that make perfect sense when viewed on a chart or an Excel spreadsheet are self-evidently ludicrous when you consider the human beings that the numbers represent.

While devolution of greater powers to the UK’s major cities is to be welcomed, the power must be devolved to recognised levels. People know what Manchester is, and at a push they could get behind the idea of the Greater Manchester conurbation. The same can probably be said for Birmingham. But ‘Manpool’ or the West Midlands Conurbation are places that exist only in the minds of civil servants and economists.

This is where a politician’s mind is required in addition to that of an economist. Great cities need more than the perfect mix of investment, local skills and natural resources. There is an element of civic identity, the fact that being a Londoner or a Mancunian or a Brummie is a clearly identifiable term and means something, which must be considered as well as the cold hard calculations as to what makes an ‘optimal’ self-governing urban unit.

Unfortunately, this fact seems lost on O’Neill, who takes his consolidation proposal to even more objectionable extremes:

One could easily apply the same logic to other cities close to each other, such as Derby and Nottingham, or Newcastle and Sunderland.

Following this logic to its ultimate conclusion, we would be better off if we treated the entire United Kingdom as one giant conurbation, a single vast city-state. The UK could devolve power to itself, and under unified authority it would enjoy better coordination of projects and higher economic growth. This is clearly preposterous.

Nonetheless, Jim O’Neill has proposed half of a good idea. The UK’s major cities need to strengthen their individual identities and improve their economic vibrancy. Devolving more power to them could only be a good thing, if only the seemingly inbuilt British resistance to variety and fear of the dreaded ‘postcode lottery’ could be overcome.

But rather than wasting fruitless hours in committee trying to come up with a catchy, memorable name for the new NorIpsCamWich Urban Region, let’s just use those handy city names conveniently handed down to us by history and actually recognised by the people who live in them.

After all, there’s no point in creating extra work.