It's a fine sentiment but there are a dozen different game theory principles that contribute these investments never getting made when left in the hands of the private sector. If you're upset about not reaping any of the benefits of your tax dollars, just buy the S&P 500. Of course you don't want the government investing in bad ideas but that doesn't seem to be your sticking point.

FWIW I don't think the status quo is ideal, the government should be getting more credit for and more value out of research that results in profit for private companies so it can invest in and lessen the tax burden of future research.