In Nick Bostrom's paper on the survival of humanity, several potential catastrophe scenarios are technological ones. That makes me think that it might actually be a bad idea to popularize science.

The irony here is that information about how to create a catastrophe - how to make a nuke, how to construct viruses in a laboratory, how to make a nanobot - is just about the only scientific information that people are hiding. (Fortunatetly, though, they don't make a big deal about the fact they're hiding it.)