American eight-inch cruisers against Admiral Graf Spee

Did the US Navy have a cruiser capable of dealing with Admiral Graf Spee?

Yes; any of its eight-inch heavy cruisers could probably have fought the German raider effectively, although none actually encountered her.

The historical US Navy did not send a ship into the River Plate action against Admiral Graf Spee. American heavy cruisers were nevertheless capable of meeting the German raider. Their eight-inch batteries supplied the necessary hitting power. The scenario separates an unrealised match-up from the material ability to fight it effectively.