The supreme law of the land grants the federal government no authority over intrastate commerce. Whatever the right answer to CA's winking at violations of CA law may be, federal involvement ain't it.
Methamphetamine is FDA approved for the treatment of ADHD and exogenous obesity. It is dispensed in the USA under the trademark name Desoxyn.
Before you say, there is a law against producing it because it....safe...blow up...yadda, yadda, yadda...consider; In the same jurisdictions where "medicinal use of cannibus" is legal under the supervision and prescription of a doctor, it is illegal to grow marijuana for the purpose of distribution. State law, not federal law.
Any way you cut it, at the federal level or state level, the law is a joke. If you think that pot is not imported for sale and distribution in California from out of state, you are goofy. If it is being imported for consumer use, guess what. It's now interstate commerce, kinda like corn (remember the farmers). The state starts the farce. The Federal State DOJ rightfully stays out of it.
But the overspending, over-regulating FDA sticks it's nose in everything from vitamins to ecoli. Why not pot?
I appreciate the civility of this lively debate. Only intellectual conservatives can converse at this level. :o)
In case duty calls and I have to return to work, you and yours have a very Merry (herbal) Christmas. Lol.