No, they aren't. The United States of America was founded before their inclusion. They are significant to the expansion of the United States of America. In fact, Texas was a sovereign nation independent of the U.S. and Mexico for ten years and similarly California was also an independent Republic though only for less than a month before being included.
The United States of America was not founded with 50 states nor can the realization of the Manifest Destiny be included in the "founding" of the nation.
|