I don’t feel your metaphor quite fits, and there is no one definition of a country - especially not for the time period. You can play semantic games about whet

I don’t feel your metaphor quite fits, and there is no one definition of a country - especially not for the time period. You can play semantic games about whether the nation was a nation at the point Arnold betrayed it, but he made a conscious decision to betray the Continental Army so really this is just splitting semantic hairs. The man is the quintessential turncoat.