The stock market is supposed to be for long-term investment to help fund business enterprises. A whole new industry was arisen which analyses stock price changes from second to second and makes profits off the fluctuations in the market. This industry does nothing to increase the wealth of the nation. These very short term "investments" do not help fund businesses. They are essentially a hidden taxation by the traders on the investments of the public. They also add to the volatility of the market.
Adding a tax of one tenth of 1 percent would not make any significant difference to long-term investors. It would serve to discourage speculation and computerized trading. It would also reduce the fluctuations in the stock market. Finally it would help balance the budget.