I agree with you 100%, slingblade. In the early 60s the "gateway" idea was passed on quite frequently and was accepted as gospel. The rationale for this was the notion that, "a majority of heroin users first tried marijuana," but that doesn't prove a thing since the majority of heroin addicts probably also drank milk as children.
If marijuana were indeed a "gateway" to stronger drugs why aren't there more heroin addicts or crackheads, or meth addicts? If marijuana is a "gateway" drug couldn't we assume that the marijuana users of today are the dangerous addicts of tomorrow?
It's as preposterous a claim as, "all beer drinkers will eventually turn to harder liquor (whiskey, scotch, gin, etc.)."