Weird theory my boy. -- Where did you dream up that one?
-- Can you justify it with ~any~ link to our founding documents or common/case law as practiced in the USA?
I challenge you to make a rational argument supporting your theory.
My theory? It's not a theory it's fact through logic. Same way that either you can be a member of FR, or not. There is no half and half. If you are signed up for FR, you are a member, if you aren't signed up then you aren't. Logic.
So, either the constitution allows for states to regulate harmful substances by prohibiting citizens from owning it, or it doesn't. Your post by Rehnquist seems to imply that they can. So, the qualifier is, what is too dangerous and who get's to decide?