How does the author suggest the manifest Destiny is not a noble as Cordelia makes it out to be

the authors suggests that

As the manifest destiny is a belief that states it was God's will that Americans spread over the entire continent, and to control and populate the country as they see fit. in fact, it was used before civil war to validate the acquisition of continental territories like oregon, for example. This is the central idea that the author suggests by Cordilia's ideas in her letter.