Fusion burns hydrogen, yielding helium, an inert gas of some commercial value. The oceans are 20% hydrogen by weight, so we will never run out of fuel. No radioactive wastes. No carbon emissions, if that is important to you. Fusion research has been ongoing for the last 50 years with little success so far.
Now two small projects, the Polywell project and the Fusion General project might produce workable fusion reactors. Both projects are small and cheap. A few million dollars of funding would accelerate both projects.
With the rewards so great, and the costs so small, the funding is worthwhile, even if the odds of success are unknown. It's a better use of taxpayer money than bailing out brain dead banks and auto makers.