The most accurate response regarding the role of Manifest Destiny in the westward expansion of the United States is: Settlers believed it to be the destiny of the United States to expand west to the Pacific Ocean, justifying their actions at the expense of American Indians.
Manifest Destiny was a widely held belief in the 19th century that the expansion of the United States across the American continents was both justified and inevitable. This ideology often led to the displacement and suffering of Native American populations as settlers moved westward.