Where Scotland led, Britain’s biggest cities are following. Not to independence, but towards radical devolution that their leaders claim is the key to a sustainable increase in growth. This claim is untested, but worth testing. The political case for devolution to the country’s ten “core cities”, as they call themselves, is even more compelling. The Scottish devolution promised at the time of last year’s referendum demands nothing less.

Britain is the most centralised advanced economy in the world. Central government’s share of total public spending is twice as large as in France and nearly four times that of Germany. Just 3 per cent of taxes are raised locally. In Liverpool, 95 per cent of public money spent is channelled through Whitehall. There, and in every other conurbation, too much tax is wasted.

The central proposition of yesterday’s cities’ summit in Glasgow was to use a deal already struck between Whitehall and Manchester as a model for up to nine more similar deals, from Leeds and Liverpool to Newcastle and Glasgow. Clusters of city councils, headed by elected mayors, would raise and spend more taxes locally. If Danny Alexander has his way, these taxes could include stamp duty, worth up to £7 billion.

This scheme would go beyond the “northern powerhouse” promised by the chancellor and entail a fundamental shift of power away from Westminster. It would improve local accountability. It could boost growth and cut waste. Most importantly, it would help to meet the requirements of fairness after the referendum in Scotland. Devolution there may save the Union but it will create a chronically imbalanced system of government. William Hague’s proposals for an English veto on English-only issues are unlikely to be the last word on the subject. Reviving our great regional cities by easing the dead hand of central government can only help.

The “devo met” scheme floated at the cities’ summit was pitched as a homage to the barons who presented Magna Carta to King John 800 years ago. In reality it is a cautious return to serious reform of regional government after the more recent failure of less serious efforts. In the 1980s, Ken Livingstone and Derek Hatton made city government in Britain a byword for militancy and political corruption. A decade later, new Labour’s misconceived plans for regional assemblies were greeted by voters with indifference.

The Manchester model is more auspicious, for three reasons. It is economics-led, based on the theory that public money is a better stimulus if pooled and spent locally than handed out by central government which usually fails to co-ordinate its efforts. It has had cross-party support from the start, notably from Sir Richard Leese, the Labour council leader, and Greg Clark, the Conservative minister for universities, science and cities. And it is incremental, with money and power ceded by Whitehall gradually and on merit.

The deal agreed last year means a modest extra £1 billion for Manchester to spend on local transport and services by 2017. Similar devolution to all ten of the country’s biggest conurbations would mean the transfer of about £14 billion in the short term but could, they claim, add £222 billion to national GDP by 2030. Such figures may prove fantastical but it is clear that too many British cities are failing to fulfil their potential. It is time for Whitehall to let go.