The best place to invest your money including tax dollars is in the company with the highest chance of success. For many reasons I believe Tesla will disrupt the car industry and lead the transition to making the electric car the new standard : amazing founder, 100% focused on the electrical car, the best technology (with a true viable range),a good financial situation, good early traction and a sexy car!
Electric cars are an order or magnitude simpler mechanical devices as compared to IC engine cars. Once an affordable battery chemistry (or any other cheap energy storage mechanism) is figured out, a lot more electric car companies will get started (I am hoping for a healthy 'car-kit' market). Tesla is the 'best' in the sense that it has the best technology to handle the idiosyncrasies of Li-ion battery (they like to burn themselves the first opportunity they get!).
Is the government going to see a return on those? Or is it an investment because you think they are going to be a net improvement for society? To be honest if I had a choice I would give most tax dollars to the EFF and ACLU, but if Tesla can improve battery technology and adoption of electric cars I would consider it a win.
