Why Americans Wanted to Annex Texas: Manifest Destiny & Cotton

The push to annex Texas (achieved 1845) was driven by two powerful, intertwined forces:

1. Manifest Destiny

The belief that the U.S. had a divine right and duty to expand across the continent—spreading democracy, Protestantism, and "civilization" from Atlantic to Pacific. Texas, as a vast, independent republic on the southwestern frontier, was the obvious next piece.

2. Economic Interests (Especially Slavery-Based Cotton)

• Land for Cotton: East Texas's fertile soils were ideal for short-staple cotton, the engine of the Southern economy.
• Expansion of Slavery: Southern planters saw Texas as a new frontier for plantation agriculture using enslaved labor—critical to maintaining political balance (free vs. slave states).
• Trade Routes: Control of Texas meant access to Gulf ports (Galveston) and overland routes to Mexican markets (Santa Fe Trail).
• Speculation: Land companies and politicians profited immensely from cheap Texas land grants.

Additional Factors

• Strategic Security: Prevent British/French influence in an independent Texas.
• Nationalism: Victory in Texas Revolution (1836) fueled expansionist pride.

Annexation triggered the Mexican–American War (1846–48), adding vast territories—but also deepening the sectional crisis that led to Civil War.