The main thing preventing nuclear is lobbying from fossil fuel energy companies and petroleum exporting countries. You often hear anti-nuclear claims from environmental groups, but follow the money and see who is financing them:

https://www.europarl.europa.eu/doceo/document/P-9-2022-00127...

But they lobby against anything that could practically reduce dependence on fossil fuels. If you want to do anything about it you have to overcome that, and it's no different for nuclear than it is for any other part of the solution.