Further, would punitive income tax rates on bonuses and City incomes in general actually matter?
On the one side we've all those who would soak the rich, come what may, and who then dress up their denials that tax rates matter. People don't want to leave London or Britain (as thouroughly colonial an idoocy as you will hear in the modern world, that us, our way and our place is so wondrous that everyone is just delighted to be here), people don't move for tax reasons, anyway, where would they go and all that. Even as far as saying that Zurich is such a boring place, who could ever want to live there?
On the other side are all those still rational enough to recall that people do indeed respond to incentives.
So, is there any way in which we can actually quantify how much of the City we might lose if we do carry on trying to overtax it? Actually, yes, there is, for we've another international market in highly paid testosterone fueled young men: football players. And when researching such we find that:
Combining the evidence from tax reforms in all 14 countries in our sample, we find that the location decisions of players are very responsive to tax rates.
"Very responsive" note. Not mildly, not just a little bit, but very. And as our researchers go on to note:
Second, our results matter for policies much more broadly in the sense that they demonstrate for the first time a clear effect of taxation on international migration and sorting of high-skilled labour.
Quite. If it is possible to tax Christiano Ronaldo off our shores, as the researchers moot might have happened, then the really rather brighter denizens of the City can also be taxed into emigration.
And leaving aside the idiot wing of the Labour Party who really would like to eviscerate our largest export industry, there's no one who would be happy with that outcome, is there?