Before claiming that London makes much of the UK's wealth, you need to go to Dublin and realise that all the embassies, HQ' of industry etc.etc. are there, just like London.
You do not see this in Belfast, Edinburgh or Cardiff, or England's regional centres such as Manchester, Liverpool, Leeds, Birmingham, Bristol etc.
London is only apparently wealthy because it sucks blood from the rest of the country.
That's simply not true of London, I'm surprised at how little you know about this. As I've said, London does not have income from elsewhere in the UK and sucks nothing from the rest of the UK.
London does not have the UK HQs of businesses based elsewhere in the UK. Take the car manufacturers, Nissan, Peugeot, Honda, BMW, Toyota, none have offices in London. The electronics companies like Sony for example, HQs elsewhere. Even Rolls Royce Aero Engines only have a London regional corporate office HQ for UK corporate business, basically the financial stuff. All their business offices are scattered elsewhere, even their defence division that one might think would be in London is in Bristol.
The HQs we have are mostly of foreign or one-time foreign companies and companies operating overseas, and even what we have the government keeps taking from us and moving them to the needy regions.
In my own borough the latest such loss is Swiss company Nestle persuaded to move it's HQ out, losing my borough almost a thousand jobs, a huge blow. Formerly my borough has had many such losses, we at one time had Dutch company Philips Electrical UK HQ and TV manufacturing and numerous smaller foreign and British company industrial operations.
At one time in the last sixty years London manufactured cars, vans buses, coaches and trucks, we made all our buses up to and including the Routemaster and our own London Underground trains. We had almost all the key coachbuilding companies like Duple, Park Ward, H J Mulliner, Hooper and Barker making luxury cars and coaches for the world. We even made aeronautical equipment and missile components and at one time I worked on the latter in inner London. All of it has been taken elsewhere by government persuasion and back door subsidies, and much of it since lost by those other areas. But we still have the UK's only mass production bicycle factory, Brompton, who have stubbornly refused to move out and export to the world from here.
Of course it's not only London that has suffered this, any area that dares to be successful can get hit the same way. The West Midlands has long suffered in the same way, from long ago when the Rootes Group were persuaded to shift Hillman Imp production to Scotland through to the recent persuasion that resulted in the BMW Mini made elsewhere, they've lost out. Luton too with it's successful Vauxhall company had the bulk of car production moved to Ellesmere Port, a needy area.
Of course we have the embassies in London, but that's peanuts income, London's £56 billions income from international financial services dwarfs such trifles.
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