The Northern Powerhouse is quite hard to describe. That is because it does not yet exist: it will take time to join Manchester, Liverpool, Leeds, Sheffield and Newcastle into a “mega city cluster” with a population bigger than London, and a growth rate comparable to the south of England.

But as a political project, the Northern Powerhouse does already exist. It is led by George Osborne, who has staked his political credibility on making a success of it, and it enjoys the strong support of Sir Richard Leese, since 1984 a Labour councillor and since 1996 the Leader of Manchester City Council.

In 2017, Greater Manchester will elect its first metro mayor, to whom will be devolved from Whitehall control of the budgets for transport, housing, the police and, biggest of all, health and social care.

The terminology here is confusing. Greater Manchester is a metropolitan county, created in 1974 as part of what some of us still think of as the infamous Heatho-Walkerian reforms.

It contains ten metropolitan boroughs: Bolton, Bury, Oldham, Rochdale, Stockport, Tameside, Trafford, Wigan and the cities of Manchester and Salford.

During the general election, when I visited the highly marginal seat of Bolton West for ConHome, I met older voters who expressed, without being asked, their continued annoyance at being lumped in with Manchester.

They were also pretty annoyed with the Labour Party, which they reckon has failed them during many decades of dominance of the north of England, and a still quite recent 13 years of power at Westminster.

One of the many things Bolton West lacks is adequate roads. And as Sean Anstee, the Leader of Trafford Council, pointed out to me when I spoke to him this week, those roads do not stop at the borders of Bolton West.

Trafford is the only Conservative borough in Greater Manchester, but Anstee sees great opportunities for growth in the Conservative vote. Greater Manchester elects 27 MPs, of whom only two were Conservative in 2010, a number which rose to five in 2015, when Bolton West was one of the gains.

But in 2017, when the first election for the Mayor of Greater Manchester is held, Anstee sees the chance for wasted Conservative votes in even the safest Labour seats at last to become once more meaningful. He says the party needs to think seriously about how it will approach that election.

The Northern Powerhouse amounts to a powerful critique of previous Labour policy, which was to try to revive the region by spending more public money and distributing low-paid public-sector jobs. After many years of that approach, grievous areas of deprivation remain.

In the southern part of Greater Manchester, 27,000 new jobs have been created in the last ten years, but in the former mill towns in the northern part, only 2,400 new jobs.

The Northern Powerhouse is a clear demonstration that for the Conservatives, that record is nothing like good enough.

The most blinkered Labour people will never accept an idea that comes from Osborne. But the Northern Powerhouse offers Labour leaders who know their own party’s record is not good enough the chance to develop the region, not just sit around moaning about savage Tory cuts.

In the Comprehensive Spending Review, one can be confident that the Chancellor will demonstrate his support for the Northern Powerhouse. The project was mocked after the general election when electrification of the line from Manchester to Leeds was “paused”: yesterday, however, it was “unpaused”, and mockery became rather more difficult.

Between now and 2020, the Conservatives can make it harder and harder for the charge to stick that they are content with London’s preponderance, and only really care about rich people who live in the south of England.

On Osborne’s recent visit to China, he took Labour council leaders from the north of England with him. Leese wrote during that trip:

A few days in China doesn’t half help put the relevance of the Northern Powerhouse concept into perspective. The North of England has around 15 million residents, its major cities, Leeds, Liverpool, Manchester, Newcastle and Sheffield (including their whole city region areas) 10 million. If you draw a triangle with Newcastle, Sheffield, and Liverpool as its corners, the land area covered is less than that by the cities of Beijing or Shanghai on their own. Chongqing’s 30million people live in a city the size of Austria.

On the other hand, if you look at the economy of the North of England, at £290 billion per annum GVA, it is larger than that of Denmark or Sweden. Premier League football is a great door opener here, but though everybody seems to know about Manchester City and Manchester United, they don’t in general know much more about our city, and we are pretty tiny compared to even medium size Chinese cities. If we succeed in getting the transport investment we want over the next ten to fifteen years to get the sort of connectivity that we want between the northern cities – connectivity that will help us create the virtual super city of the North – then as a virtual city of 10 million people, a city bigger than London, we begin to register.

As soon as one starts to read about the Northern Powerhouse, one comes across the fashionable idea of “connectivity”: the idea that by linking these different cities up, so they can be treated, if one wishes, as a single city, the rate of economic growth will increase.

We shall see how much difference connectivity makes. Some of the jargon that goes with it sounds like mere window-dressing. But unconnectivity is probably not a brilliant idea.

One of the pleasures of going to the Conservative Conference in Manchester will be the chance to wonder at Manchester’s sublime gothic revival Town Hall, designed by Alfred Waterhouse and finished in 1877.

John Ruskin called the Great Hall in that building “the most truly magnificent Gothic apartment in Europe”. It is adorned by 12 murals by Ford Madox Brown depicting the history of Manchester, including one of the opening of the Bridgewater Canal in 1761, which carried coal barges into the heart of the city.

That was an earlier form of connectivity. If Manchester had not been linked to the outside world, it would never have become a cradle of the industrial revolution. And it is hard to imagine that Greater Manchester will revive without once more becoming, as an expression of local leadership and enterprise, far better connected.