I think I read in the 90s that made-up child porn (such as drawings from imagination) had recently become illegal in the U.S. It doesn't seem like that could've

I think I read in the 90s that made-up child porn (such as drawings from imagination) had recently become illegal in the U.S. It doesn't seem like that could've survived a first-amendment challenge, but IANAL and I don't know what's the status now.