So, back to individual States with a quasi-nation in affect. The term United States of America was a term used for the Articles of Confederation, which remained until the Constitutional Convention in 1787 which re-designed the Articles of Confederation. That was the formal birth of the United States of America that the World accepted as a sovereign nation. Don't trust me?...Google.
Opening line to our peace treaty with Great Britain, the Treaty of Paris 1783:
ARTICLE I.
His Britannic Majesty acknowledges the said United States . . .
Please stop embarrassing yourself.