Isn't this nation's capital the District of Columbia? Americans did use some of the great navigations heritage in order to create some national symbols.
Yes, but in an homage - nobody claims that Columbus was American/"One of us". (Or if they do, they deserve a scowl).
And why is it any different from the Macedonian situation?
I do not claim to be an expert on Balkanic Nationalisms, but I never heard anything about a Macedonian claiming that his country was founded by Alexander the Great.
They literally rename airports and build statues of Alexander and his father, claiming to be their descendants. Pella Square (after the old capital of the Kingdom of Macedonia in Greece).
However, Americans have a pretty well documented timeline of heritage from English settlers, alongside slaves, Germans, Italians, etc. They don't claim to be Italian, or German, but American (Of X stock perhaps).
Meanwhile... Macedonia isn't in the right place, it doesn't speak a language that could even be said to be descended from or related to Macedonian or a language in the same family.
PLUS - There is already a group of people who claim that legacy - with more backing them up in that regard.
My understanding now is that the Greek position is basically "Look, you ain't descended from Ancient Macedon, you're slavs, you came and invaded hundreds of years ago - sure, name yourselves after the region you're in
NORTHERN Macedonia. But don't go and claim our heritage thank you, it isn't yours. Be Hellenophiles as much as you like, but you are the people who live in Northern Macedonia. Not Macedonians."
By and large - that sounds reasonable to me, and unless there is some evidence of Macedonian ancestry that I haven't seen, it sounds like the argument that wins.
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Meanwhile, back to the threads OP - I am intrigued as to whether a Neoclassical Romania (in a more obvious way than IOTL) could set itself up early enough to set up a whole mess of Neoclassical Myths, or a wishful thought of unifying together in a federation based on territory and recognising individual differences, but collective defensive needs. (nicely circumventing the FYROM issues, and Yugoslavia) in favour of a Federation of Haemus (the old term for the region). If they could set that up based on a shared Neoclassical+ narrative, it could be pretty awesome. (Essentially a way for them to 'erase' their recent history of misfortune and subjugation).