Some folks feel like the war on drugs infringes upon their freedom of religion. There have been some exceptions made [1], but the general populace is prohibited from using substances that have been used entheogenically for thousands of years[2][3].

It's a shame that our founding fathers didn't explicitly spell out a right to the dictate the contents/state of your own mind. Perhaps it is implicit in the other rights: what good is freedom of speech and religion if I'm not allowed to enter a contemplative state of mind in which I could have significant insights about my life and spirituality?

[1] http://en.wikipedia.org/wiki/Religious_Freedom_Restoration_A...

[2] http://en.wikipedia.org/wiki/Peyote#History

[3] http://en.wikipedia.org/wiki/Psilocybin_mushroom#Early