Final answer:
The provided literature reflects the complexities and contradictions in America's formation, where the ideal of a united society was undercut by prevalent racism and exclusion, highlighting the ongoing struggle for true democracy and equality.
Step-by-step explanation:
Michel-Guillaume Jean de Crèvecoeur's observation about America as a melting pot where a new race of individuals from all nations was being formed reflects an idealistic vision of a united and inclusive society. However, this ideal was challenged by the realities of the era, including racism, exclusion, and brutality towards indigenous peoples and non-white individuals, as the literature from the period reveals. The quote by John O'Sullivan speaks to the concept of American exceptionalism and manifest destiny, whereas other texts like those of Jefferson and Du Bois highlight the divisions, struggles, and aspirations for a true democratic society that includes all races and acknowledges their contributions. In considering these works, we recognize that while the ideals of liberty and democracy were foundational in America, they were also marred by the exclusionary practices and systemic inequality of the time, which resonate with ongoing issues of race and identity in contemporary society.