Immediately after the end of World War II, the Greatest Generation was absolutely convinced that they were entering the Atomic Age and that it was going to be the best thing since sliced bread.
That's because they didn't know much/anything of the problems/risks with nuclear power plants. Nuclear power did seem like this amazing new technology straight off the pages of a science fiction novel and it had ended the war. Of course they were interested. There was a substantial lag between learning about it and what it could do and then figuring out what the risks and problems with it were. Over time we learned that there were significant practical problems with fission as a power source and some very real risks and it took a while for the public to absorb this argument.
People are by nature bad at evaluating risk (we tend to be risk averse) so it's hardly surprising that eventually public opinion in many places swung against nuclear power over time. Public opinion of the risk of nuclear power demonstrably is at odds with the real objective risk but if you want to build more nuclear fission plants then you need to deal with that very real fear in the political arena.
Then Green Peace set themselves against it. They spent the '60s and '70s telling the world how dangerous nuclear power was...
Greenpeace was a small player in a much bigger drama and I think you hugely overestimate their influence in this debate. But even if we stipulate to what you are saying, it is absolutely true that nuclear fission as a power source does carry substantial risks. To pretend that these risks don't exist would be foolish. You cannot argue that fission is 100% safe or that catastrophes cannot happen and remain credible. There isn't a fission power plant we've ever made that doesn't carry real risks and doesn't required oversight and maintenance from humans. Even simple designs like RTGs carry meaningful risks.
Then in 1986, the Chernobyl disaster happened, the greatest gift to anti-nuclear forces since the bombings of Hiroshima and Nagasaki.
The reason Chernobyl was/is scary is that there is currently no way to prove that a similar disaster couldn't happen again elsewhere. It was confirmation of an already existing fear. There is not a single fission plant in operation today that does not have failure modes with potentially severe consequences. The failures are mostly remote but potentially very severe and that is the sort of risk we as humans are worst at evaluating. Use airplanes as an example - they are objectively very safe and yet many people are absolutely terrified of them because some of the failure modes are potentially quite severe and out of their control. Until you can trot out a scientist that can show that a meltdown or radiation release or similar disaster is provably impossible you're going to have a hard time getting public opinion back in favor of nuclear fission in many parts of the world. And even then a lot of people won't believe the evidence. I probably find that as disappointing as you do but it's the reality we live in thanks to human nature.
Human nature is to be scared of the things we're told to be scared of
And we've been told (with some justification and evidence) to be scared of fission for decades now. That's already done and reversing it is going to be really hard thanks to human nature. Getting people to accept something new is a lot easier than getting them to stop fearing something familiar that they think (rightly or wrongly) is dangerous.
For the record, I'm actually in favor of increased use of fission to reduce our dependence on fossil fuels. But to pretend that it is without risk or that it will be politically easy is just foolish naivety.