How can something be prohibited against if it doesn't yet exist? How can you make meth illegal prior to its manufacture? Obviously, that has nothing to do with it. The fact is that meth is outlawed after its been made crystal clear the effects of the drug on the human body.
Your response makes it clear I've not communicated my point to you.
Meth (among other drugs) exists as a regularly taken recreational drug because of prohibition. I'm not talking specifically about the prohibition of Meth in particular, but drugs in general. If it weren't for prohibition, people would instead be taking much safer (and apparently more enjoyable and controllable) drugs such as Cocaine or Opium. If these were legal, and regulated, then instead of taking dangerous, unpredictable and often adulterated drugs people would tend to stick to safer, more enjoyable and more controllable highs.
Which exactly mirrors what happened with alcohol prohibition. During prohibition people tended to drink Moonshine - which frequently contained both Methanol and fusal alcohols (which are distinctly more harmful than Ethanol), was of largely unpredictable strength and was often adulterated with other liquids. What's more it was vile, vile stuff - which is why after prohibition it pretty much disappeared.
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