What idea is associated with the concept of Manifest Destiny?

The concept of Manifest Destiny is fundamentally about the belief that American settlers were destined to expand across North America. This idea surfaced in the 19th century, rooted in the notion that the United States was not just entitled but destined by God to spread democracy and capitalism across the continent. It was tied to a sense of mission and purpose, which many Americans felt justified the expansion into territories that were already inhabited by Native Americans and other nations.

The belief in Manifest Destiny played a significant role in justifying westward expansion, territorial acquisitions such as the Louisiana Purchase, the annexation of Texas, and the Oregon Trail migrations. Proponents of this ideology saw expansion as a means to enhance the nation's strength and influence and felt a moral obligation to spread their perceived superior way of life.

The other options do not capture the essence of Manifest Destiny as accurately. While the notion of cultural superiority might be tangentially related, the central idea is indeed the belief in destined expansion. Isolationism contradicts the very premise of Manifest Destiny, which advocates for engagement and territorial growth. Similarly, the belief in equal rights for all citizens does not directly relate to the expansionist agenda characteristic of the Manifest Destiny philosophy.