True sustainable > Nuclear > Fossil fuels
Transitioning out of fossil fuels is #1 priority. Whatever it takes. Even shortening the transition by one year would be worth 40 more years of nuclear wastes, which are much much more easily manageable problem (unlike CO2 you can literally store nuclear waste in a hole for thousands of years without it messing up the environment)
My long term preferred solution is renewables or fusion, but we are not yet at the point where we can deal with the intermittence (but closing that gap fast)
I am really angry at the anti-nuclear movement. If we had gone all-in in that direction in the 90s we would be out of the fossil fuel economy by now.