I picked this up today, have been looking at it for a bit. I can see letters but not what they are (the N and O are part of the design.
The slogan dates back to the late 18th century. Specifically the XYZ affair in I believe 1798 when French officials demanded bribes from the US representatives to allow them access to the French Cabinet Ministers, also from the tribute demands of the Barbary Pirates. We had paid them tribute for years but then eventually they went ahead and captured our vessels anyway and demanded even more money. This angered the people leading to the slogan. It also drove us to sending in the Marines to clean out the pirates. That is where the phrase "to the shores of Tripoli" comes from in the Marine Corps Anthem. The slogan was resurrected on the hard times tokens and later on Civil War tokens