EU Robin Hood Tax?

For several decades, the European Union has considered imposing a tax on all financial transactions (stocks, bonds, derivatives, etc.) executed amongst the participating countries. When Nobel Prize winning economist James Tobin first developed the tax, the revenue was to be used to combat environmental and humanitarian problems. Now the potential tax will be used to punish the financial sector for the crisis that Europe is currently in:

 "Taxpayers have legitimate expectations that they will be paid back for what was used in the bailouts, and the financial transactions tax can provide for this… Many citizens are angry about these problems over the causes of the financial crisis, and this small contribution of very tiny rates could help rebuild confidence in the financial sector," [Algirdas] Semeta said.

The UK is particularly against this tax because it believes that London will be the victim of a negative externality in that business will be driven away from the city. In reality, London will be the benefactor of a positive externality because transactions that occur within the UK or between the UK and a nonparticipating country will not be subject to the tax. This will bring more business into London, as well as the United States, as investors will look to avoid the taxes. This will inevitably decrease the projected 57 billion euros ($74 billion) that the tax is supposed to raise annually and not add the hopeful 0.5% to the EU’s GDP. For comparison sake, if the US instituted this tax solely on transactions within the NYSE, it would raise $20 billion monthly without taking NASDAQ, bonds, or derivatives trading into account. A quick, clean way to tax the wealthy and help balance the fiscal budget or would it also just push business away from the US?