Bottom line: i believe i am sufficiently capable of correctly interpreting the intent of a document written in my native language, and i am quite certain that this document forbids any government entity from committing injustice against its own populace (though not sure about external populations...).
In order to sufficiently legitimize cannabis prohibition, the aforementioned assertive interpretation must be defeated, in favor of the constitution not protecting my human rights, and not forbidding government entities from committing injustice against us, the populace.
However, if you do indeed manage to make an impenetrable argument in favor of tyrannical selective interpretation of the apparently meaningless (or only selectively meaningful) constitution, i will counter-assert that when any governing body manages to successfully defeat the constitution, this is no longer The United States of America, and so i am not bound by whatever regulations the invading country insists on imposing, regardless of the fact that i know violent consequences will be used against me for noncompliance.