How Americans justify expansion from coast to coast?

Americans justified expansion from coast to coast through the ideology of Manifest Destiny, which held that it was their divine right and duty to spread democracy and civilization across the continent. This belief was often accompanied by the notion that American culture and institutions were superior, leading to the idea that expansion would benefit both the nation and the territories acquired. Additionally, economic motivations, such as the desire for land, resources, and new markets, played a significant role in supporting the expansionist agenda. This justification often overlooked or dismissed the rights and cultures of Indigenous peoples and other nations.