Reply #118: Actually, it's not silent at all

[Occulus]

The 9th Amendment says this:

Amendment IX

The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people.

It explicitly spells out that rights of the people not enumerated to them in the Constitution are nonetheless still the rights of the people. Therefore, the right to voluntarily imbibe, ingest, or inhale any foreign substance could be said to actually be granted by the Constitution, thanks to the 9th Amendment.

This would be why an Amendment was necessary to prohibit alcohol- the law would have been unconstitutional otherwise. Just like the drug laws are today.