For many years – in fact, for centuries – England's two great north west cities, Liverpool and Manchester, saw themselves as competitors. They fought – almost literally – for both investment and prestige.
But this has changed and they now realise that, in the modern economy, they can be – and are – partners.
What is good for one is good for the other. Both cities benefit as a result.
It should be a similar story for Londonderry and Belfast. Not – I must stress – that Derry sees itself as a competitor to Belfast.
Our city is not seeking to challenge Belfast's rightful role as Northern Ireland's capital city.
But Derry does want much more inward investment, greater growth among its indigenous enterprises, more tourism revenues.
The point, though, is that, just as the wonderful investment going into Belfast is good for all of Northern Ireland, so, too, a more prosperous Derry is good for Belfast and for the rest of Northern Ireland.
Our city wants not just to pay its way, but actually to contribute tax revenues to the rest of Northern Ireland and the UK.
Our city has remarkable strengths. We have a spirit and a new-found cultural confidence that is infectious. We have a natural beauty and quality of life that is as good as anywhere.
And we have a telecommunications infrastructure that is not merely the best in the UK, or Ireland, but also provides the highest connectivity speeds with North America of perhaps anywhere in Europe.
That physical fabric fits perfectly with the economic strategy of our city, which focuses strongly on digital and creative businesses.
We are developing a fast-expanding new technology cluster. We are aided by long-standing businesses, such as Seagate, Allstate and Kofax.
But we also have some of the most exciting young digital businesses of anywhere in Europe, including Learning Pool, 360 Production, Dog Ears and Smalltown America.
This digital hub has many similarities with the commercial renaissance of Belfast, much of which is also based on the new technologies and which has its own cultural hub.
Much can be gained from connecting these two hubs in a more intimate way. For this to be achieved, two things need to take place – which happen also to be the steps needed to create a positive transformation of Derry's economy.
The first is that our transport system needs to be brought into the 21st century. We need a road connection between Belfast and Derry that is fast and efficient. (Derry also needs a fast road link with Dublin, but that is a point for another day.)
Secondly, we need a substantially expanded university presence, producing the skills needed for our digital hub. It is wonderful that we have the University of Ulster's Magee campus, but it is much too small.
Magee's research on intelligent systems is world-leading and the recent £5m investment in brain-mapping technologies is a sign both of the cutting-edge work that is taking place and how that research and development has the potential to spin-off beneficially into the wider Northern Ireland economy.
The potential for further ground-breaking innovation and the associated skills help explain why the Londonderry Chamber of Commerce has so enthusiastically backed the campaign for Magee's enlargement.
So, make no mistake, the clear message from Derry is that it has its best foot forward – we argue a positive and productive case for economic expansion.
And that expansion will benefit Belfast, the rest of Northern Ireland, the UK and, indeed, Ireland as a whole.
Philip Gilliland is president of the Londonderry Chamber of Commerce