What was a significant factor driving America's desire for western territories during the 19th century?

The desire for western territories during the 19th century in America is closely tied to the concept of Manifest Destiny. This belief held that it was the nation's divine right and destiny to expand its territory across the North American continent. Manifest Destiny encompassed a sense of mission and entitlement that justified the expansion westward, often at the expense of Native American populations and other nations.

While western expansion is certainly a consequence of this ideology, it does not fully capture the driving force behind the movement. The notion of Manifest Destiny provided the cultural and political justification for Americans to pursue land and settle in the West.

Industrialization played a role in the push for westward expansion, as it created a need for new resources and markets, but it was the belief in Manifest Destiny that inspired many Americans to see expansion as a moral and historical imperative. Colonization refers more to establishing control over foreign lands or territories, rather than the specific American context of extending its own borders and population through self-identified destiny.

Thus, the correct answer highlights the powerful ideology that propelled America’s expansionist attitude, making it the most significant factor driving the desire for western territories during that period.