Should we need a constitutional amendment authorizing congress the power of regulating pathogenic research labs? I think most people would acknowledge that they have that power already. What about deadly Chemicals such as cyanide or strychnine? Same thing.
Marijuana looks more like a gateway to treason against the republic than to heroin.
I am not following you here. I do not understand what you are getting at. Marijuana appears to me to be just another one of those slippery slopes to worse things. If we let it in, it won't be long before cocaine is knocking at the door, and bringing all it's previously weed toking new converts.
And your solution appears to be one of the slippery slopes to something worse than that. If Anthrax = cyanide = marijuana, then hydrogen bombs = tanks = handguns. If the power of congress is public whim then we do not live in a constitutional republic, we live in a propaganda construct.