Unfounded ideas about “chemtrails” have existed for years, but now they seem to be influencing lawmakers in many states.

Three states have already passed laws banning weather modification and geoengineering, and another 28 have introduced similar legislation. Some lawmakers say they don’t see harm in enacting these bans to respond to people’s concerns, while others personally buy into the conspiracy theories.

Critics of the bans say they’re a waste of resources and warn they could hinder technologies meant to address the effects of climate change.

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