Add in leverage and say 2 billion in research could represent 10-20+ billion worth of clean energy investments before the fruits of this research could come online. And even then you would need to spend even more money actually building something useful.
This could be my own bias talking but fission has seen 100+ Billion in R&D. I have my doubts this is going to move the needle much.
PS: I am more than open to any counter arguments you have...