It takes a while to figure out what's going on.
The shops, after all, aren't immediately obvious. They don't have big signs out the front saying, "Get your marijuana here! All stoners welcome!" There are just a few judiciously placed leaves in the windows; some liberal use of tie-dye.
And anyway, you don't expect to find them in Aspen. This is a town synonymous with the finer things in life – it's more Pol Roger than pot; more filet mignon than, er, flaming bongs.
But once you chat to a few people and get the lie of the land, you realise there are now six shops in Aspen, Colorado that sell marijuana, legally. One hundred per cent legally. Six shops that are tucked away behind nondescript doors. Six shops that require ID to even enter.
And it's not as if Aspen is an anomaly within the state. Since recreational marijuana use was legalised in Colorado in January 2014, it has become a billion-dollar-a-year industry that pours about $US135 million in tax into state coffers. Large, successful businesses were created overnight.
As a traveller, it can be a little hard to get your head around immediately. All of this is completely OK? I can walk into a shop, show my ID, purchase up to an ounce of marijuana, all of which has been carefully monitored and categorised to explain its various strengths and effects, and walk out of the shop, consume it, and it's all totally legal?
The temptation, obviously, is to go crazy, to embrace teenage fantasies and get in there and purchase pretty much the entire store, to stock up on skunk, and hash, and cookies, and vapours, and gummy bears, and pretty much anything else that's now been infused with THC – including, it turns out, erotic massage oil – and take it all at once and see what happens.
This is, after all, something of a novelty. Even in the Netherlands marijuana isn't technically legal. It's tolerated. So to find that here in the USA, in the spiritual home of the War On Drugs, you can go out and buy legal weed? It's tempting.
But here's the thing about Aspen, and about Colorado, and probably about the other US states in which the drug has been legalised, in Washington, Oregon, Alaska and DC: you really don't notice any difference. You don't see the shops. You don't smell the drug as you're walking down the street – after all, it's not legal to smoke pot in a public place. And it's not like there's a noticeable behavioural problem, because stoners pretty much keep to themselves.
There are plenty of people who use marijuana in Colorado – it has one of the highest usage rates in the country. But then again, it always did. Now those people are just doing it legally, and paying taxes.
The temptation to go crazy quickly fades. The novelty of the situation wears off, and pot becomes just something else that you have the chance to spend your money on, but will probably choose not to. After all, there's Pol Roger and filet mignon to consume.
Not all of the locals in Aspen are fans of the new laws. I talked to plenty of people who would prefer things went back to the way they were, and Colorado doesn't become a destination for people who want to smoke a little legal weed.
But the fact remains that, for travellers at least, it makes very little difference. You wouldn't even know it was there unless you went looking for it. Same goes for the Netherlands, too, and Uruguay, and all those other US states.
It does make you wonder why Australia is so backward in moving forwards on this. Why is that some parts of conservative, fear-mongering USA have seen fit to legalise recreational marijuana use, to control and tax a billion-dollar industry, and we're struggling to even allow medicinal use for terminally ill patients?
Would the sky fall in if marijuana was simply legalised here, in the same way as it has been in Colorado, Alaska, Oregon, Washington and DC? The anecdotal evidence, and even the scientific evidence collected so far, is that no, it would not. People who always used to use marijuana would continue to do so. Those who never wanted to, never would.
And you only have to visit a place like Aspen to realise that's the case. To non-users of the drug it makes absolutely no difference to your daily life. To those who like a smoke, the biggest change seems to be paying tax.
Have you travelled to a state or a country that has legalised marijuana? Did you notice any big differences? Do you think Australia should follow suit? Leave a comment below.
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