up in smoke

okay, i am confused by today's supreme court ruling on medical marijuana:

The U.S. Supreme Court Monday ruled doctors can be blocked from prescribing marijuana for patients suffering from pain caused by cancer or other serious illnesses.

In a 6-3 vote, the justices ruled the Bush administration can block the backyard cultivation of pot for personal use, because such use has broader social and financial implications.
...
The decision means that federal anti-drug laws trump state laws that allow the use of medical marijuana, said CNN Senior Legal Analyst Jeffrey Toobin. Ten states have such laws.

okay, so it's illegal to grow medical marijuana in your backyard. that seems straightforward enough. so what was the reasoning?

A federal appeals court concluded use of medical marijuana was non-commercial, and therefore not subject to congressional oversight of "economic enterprise."

But lawyers for the U.S. Justice Department argued to the Supreme Court that homegrown marijuana represented interstate commerce, because the garden patch weed would affect "overall production" of the weed, much of it imported across American borders by well-financed, often violent drug gangs.

whoa, what? growing weed in your own backyard, for your own use, is interstate commerce? and not only did the supremes' heads not explode from cognitive dissonance when hearing this, but 6 out of 9 apparently agreed? (the other dissented not from cranial collapse, but because they believe in "states' rights".) so when my parents grow tomatoes in their backyard, for eatin' and givin' to friends in the neighborhood, is that interstate commerce? is the pile of clutter that has been growing in my bedroom interstate commerce?

and this doesn't make any sense either:

Anti-drug activists say Monday's ruling could encourage abuse of drugs deemed by the government to be narcotics.

"It's a handful of people who want to see not just marijuana, but all drugs legalized," said Calvina Fay of the Drug Free America Foundation.

monday's ruling was against the medical marijuana users, yes? so why would it encourage people to abuse drugs? making things illegal is supposed to deter them, right? so either about half this article was written on bizarro world or there is something else, something really significant, about this case that cnn isn't reporting.

apparently, there is a precedent that even something you grow in your yard for your own use can "affect interstate commerce" and therefore be regulated by congress. even something you grow for yourself, according to stevens, can affect interstate commerce simply because even if you aren't selling it, theoretically you could sell it. just like theoretically, because i have a lighter in my pocket, i could go out and start some church fires. of course this makes nothing resembling sense, and flies in the face of the legal principles that allow, say gun and missile manufacturers from being prosecuted everytime a civilian gets shot. if you want to try to make sense of the reasoning, you can read the ruling.

but if anyone can explain that second blockquote... how anyone with a brain could think that this ruling would "encourage abuse of drugs", please let me know.