We should absolutely be deploying fission on a wide scale, but the issues with waste disposal and radioactive contamination, while vastly overplayed, also go away with fusion.
Also, fusion could be orders of magnitude more efficient than fission, to the point where we can solve literally all of our sustainability problems just by throwing energy at the problem. Too much CO2 in the atmosphere? Build a factory that uses electricity to extract CO2 from the air, combine it with water, and recycle it back into hydrocarbons. Not enough water? Build desalination plants--the only reason we don't is because they're energy-intensive and energy is expensive. Need a sustainable source of nitrogen-based fertilizers? Extract nitrogen from the air. Batteries don't store as much energy as hydrocarbons? Manufacture EVEN MORE hydrocarbons out of the air and water and then use them to power your airplanes, in a closed-loop system where you're not even increasing the net amount of CO2 in the atmosphere.
You can make a great sustainability case with fission. With fusion, you can make an incredible sustainability case and take away all of the fears involved. And by the time we get around to inventing it, odds are we're going to be fucked enough not to have any other choice but to adopt it.
Funding a fusion program would be like buying a car while your license is suspended.