Tobin Taxes are Stupid but useful
...to the UK.
If the rump EU adopts Tobin taxes then London does very well. Germany used to do something very similiar which is one big reason why despite the German economy growing rather better than the UK for 70 years, Frankfurt is the 14th most important finance centre in the world and London is 1st.
The argument for Tobin taxes is:
They will reduce trading
They will raise lots of money because they won't reduce trading
The X billion will only hit banks because banks are nice and won't pass on the extra costs.
No one except speculators uses financial markets and pension funds, companie raising capital and selling things to other countries are figments of Thatcher's imagination.