> You also probably don't use heroin. Everyone knows it's a bad idea
About 1–12 months after using heroin, only 23%–38% become addicted [1]. Occasional and controlled heroin users do in fact exist and are documented [2]. And, most famously, the use of heroin by American soldiers during the Vietnam war was largely situational [3].So what "everyone knows" here is not very impressive. I still very strongly believe you'd be a fool or at least reckless to try heroin, but it really isn't the bogeyman people want it to be.
[1] https://jamanetwork.com/journals/jamapsychiatry/fullarticle/...
[2] https://www.drugsandalcohol.ie/3906/
[3] https://ajph.aphapublications.org/doi/pdf/10.2105/AJPH.64.12...