The fallacy that we need to give the City of London a free pass so Britain can prosper as a nation has made us all poorer. 
A recent Guardian report on Unilever's decision not to relocate to the Netherlands under shareholder pressure surprised me. The listed shareholders weren't the influential private individuals I'd anticipated, but large insurance and financial services companies such as Aviva and BlackRock. I somehow doubt their action was driven by a sense of patriotic duty.
In The Finance Curse, Shaxson quotes economic research  demonstrating that while a healthy financial services sector contributes to GDP growth, once private sector credit reaches 90-100% of GDP the impact goes into reverse; further rises simply put a brake on the economy. Instead of funding genuinely-productive investment, the finance sector just 'farms' cash in a mad money-go-round. "So the rich get richer/ And the poor get nothing", as David Ackles sang .
Private sector credit currently stands at 160% of GDP. Just a minute... where on earth did I put that list of Unilever's major shareholders?