That certainly depends on how devilish are the one you know and a random one.

Any advice on that level of generality is useless and better trashed.

The whole point is, you don't know how devilish the random one is. As bad as global warming will be, we know the risks and we can prepare for them. Whether we'll actually do that is another matter..

Getting concrete now, specifically about nuclear power, we know exactly how bad it can be. We have a very large amount of certainty about how the worst case looks like, we know very well how to prepare for some of it, and we know very well what to do to avoid the rest of it. We know those to a much higher certainty than we know the consequences of global warming. It's not a blind choice.

The only thing we don't know well is how much improvement current technology brings. We have an idea, but there are probably flaws on our estimative.

I don't think nuclear will help, mostly because it's too late. But basing decisions on ignorance is crazy.

Basing decisions on known ignorance is not crazy. In fact, I'd call it appropriate humility. It's just that the smart decision is more likely to be a "not yet / need more information" than a flat no.

Basing decisions on limited understandings is also not crazy. I've heard the rough US Army guideline is to act when you have 70% of the information. If you wait too long, there's often no right answer.

Anyway, my whole point is probably one level meta from what you're talking about. I find many disagreements turn out to be simply two different simultaneous discussions.

See, this is why we shouldn't have banned trans fats. Sure they were killing people, and sure we knew it, but the devil you know...

The substitute for trans fats was returning to butter and other natural fats, which we originally left because we thought they were so bad for us that products like margarine must certainly be better!

Thanks for making my point.

Sorry, butter is still widely (unfairly) considered evil. We replaced trans fats with rapeseed oil, soybean oil, and palm oil, which are hardly the foods our grandparents ate.

Note: I didn't say we don't know the fusion devil. We do. Just perhaps not as well as the fossil fuel devil.