Would nations stop being seperate if Earth joined a Galactic society?

Current Events

No.

Simple as that.

Even if they attain, or change to, something more like a territory or state, they will be a thing.

The primary exception is settings that have basically DESTROYED the planet.

Like, say, Warhammer 40k which somehow destroyed/removed the oceans and such during a dark period of history. And which a hero's story (the Emperor revealing himself and saying "fuck this I need to lead them myself after all") is the way the planet then unified afterwards.

I guess Helldivers works too, though I know basically nothing of their lore aside from the basic concept. For Democracy! They say, while having a feel-good description yet everyone doesn't vote, they just take quizes that ascertain who should be in charge. Actually a very good idea... if we could trust humans to not do bad things, including humans in high place.

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