Marijuana is only a gateway drug
because of it's illegality.
Imagine if we lived during prohibition. You want a bottle of wine for Thanksgiving dinner, but in order to buy it, you have to go to a drug dealer since it's illegal and not sold in stores. The drug dealer says, "Why yes, I can sell you a bottle of wine. I can also get you some cocaine to help focus your preparations, and some opium to help relax once all those pesky relatives are out of your house." In this scenario, use of cocaine and opium would go up relative to where it is now, and everyone would call wine a 'gateway drug.'
Likewise, there's the issue of relative drug strength. This scenario plays out every day in the United States:
1) Teen drinks beer. Teen gets drunk. Teen feels like crap the next day. Teen is fine the day after that. Teen is not instantly addicted to beer.
2) Teen smokes marijuana. Teen gets high. Teen feels quite a bit better the next day than he did after drinking. Teen is not instantly addicted to marijuana.
3) Teen deduces that the drug laws of the United States are arbitrarily drawn and not from any sort of common sense approach, which is true. Teen then infers that perhaps other drugs aren't any worse for him than beer or marijuana.
4) Teen smokes meth. (details clipped out) Teen dies 3 years later in a gutter.
Yes, there are very bad drugs out there. Yes they should stay illegal. Yes we should continue to prevent teens from trying them, because the very bad drugs remove your ability to make your own decisions. Marijuana is not one of those drugs, and its illegality is what creates the gateway to those drugs.
All that said, I wouldn't touch a marijuana client in California or Washington DC, even though marijuana is legal there, because the fickle whims of government have not settled down there yet. Medicinal growers in CA are still being busted by the feds, leaving all their investors and other business relations swinging in the breeze. The same is not true of Washington state or Colorado, though, because their state governments have been much more focused on developing codes and ordinances that work, and that blend well with the demands of the federal authorities.
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