An explanation from Mirada Global:
Though their prime minister, David Cameron, the United Kingdom opposed the application for the financial transaction tax. The proposal put forth by the French president Sarkozy, planned that the European Union should use said tax in order to slow down the financial speculator storm.
Cameron this way defends the interests of his country where the world’s largest financial center is active. His defence will end up having repercussions throughout the EU, for the tax to go through there has to be a unanimous vote by the 27 governments of the member nations. The proposal aimed toad a tax of 0.1% to stocks and derivatives, such as, futures or credit default swaps increase the tax to 0.01%
For Cameron, this tax, known as the Tobin Tax, is ether applied in a global level or its effects could even be negative taking financial activity to other Centers. It is not credible because not all English financial instruments can be bought outside of England.
It is quite evident that the financial sectors are protecting their interests and are in no way willing to allow their profit to be diminished. If applied all over the world this tax, known as Tobin Tax, is estimated to be able to collect 50 billion dollars a year. The proposition was invented in the 70’s before its inventor was awarded the Nobel Prize in economics. The idea consists of using the revenue from this tax in order to aid with poverty in a global scale. So the Tobin tax could have two positive effects, on one side dissuade financial speculation and on the other, finance further development.
Also available in Spanish.