It kind of depends on what the criteria are. If they mean countries that in 20 years won't have their present day borders then a lot more countries come in to play, but it's not like there won't be a country called Spain or the United Kingdom in 20 years. They might just be without Catalonia and Scotland/N Ireland.
If I had to name countries that could potentially not exist in 20 years I'd go with:
Sudan
South Sudan
Taiwan
Guyana
Israel
Maldives
If I had to name countries that could potentially not exist in 20 years I'd go with:
Sudan
South Sudan
Taiwan
Guyana
Israel
Maldives



at listing the US
They were fine before colonialism created Artificial States. Borders are constantly changing and causing conflict over everything. Africa would've been fine as a whole in the 21st century if everything was left alone



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