People would still go to WDW regardless. The location, climate and size would be the biggest reasons. The drop off of Asian tourists is because for people in Asia, a flight and a trip to the USA is very long and expensive to begin with and to Disney World, it's even longer and more expensive. That wasn't the case way back when. But now with two Disney Park Resorts in Asia and Shanghai coming soon, they can experience the Disney way in their backyard and have it more towards their tastes.
For the South Americans, Florida is not too far away. Even if a South American Disney resort were to be built, part of me feels that nothing would change. I mean, the South Americans tour groups tend to come during the summer months because it would be winter down there so if there is a large presence in WDW during the summer months, you'd have to think they loathe the cold just like people who live the Northeast and Central parts of the USA.
Anyway, I'm with crazycatperson in that it's probably not a big deal. It's only one country of 12 in South America though if Venezuela alone provided a huge portion of WDW's total profits, then the red flags would be raised.
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"All my life I wonder how it feels to pass a day, not above them but part of them.
And out there living in the sun, give me one day out there, all I ask is one to hold forever. Out there where they all live unaware, what I'd give, what I'd dare, just to live one day out there."