Chem trails I largely write off because of how ridiculously labor intensive and difficult to keep secret it would be. However, some people I consider smart kinda buy into it, and I can't deny that i often see several trails close together in clear sky, they linger and spread, and sure enough a hazy sky forms. That shit didn't happen when I was younger. You saw a contrail sometimes, and it would fizzle away trailing plane like a fuse