Final answer:
The U.S. sought Mexican territory for expansion, trade opportunities, and the establishment of slaveholding lands, but refrained from annexing all of Mexico due to racism and pragmatism. The acquisition led to substantial problems, including land dispossession for Mexicans and intensified debates over slavery.
Step-by-step explanation:
U.S. Expansion and Territorial Acquisition from Mexico
The United States was eager to acquire Mexican territory for several reasons, including the desire for land that could be populated by Caucasian Americans, westward expansion, the establishment of slaveholding lands, and the strategic benefit of controlling important ports for trade with Asia. The Mexican government attempted to keep Americans from taking over Texas by enforcing laws and military presence, but faced challenges due to the tenacity of American settlers and the annexationist mindset prevalent in the U.S. at the time. The U.S. was particularly interested in controlling California due to the potential for trade with Asia through strategic ports such as San Diego and San Francisco, as well as the agricultural richness and eventual discovery of gold, which led to the famed California Gold Rush. However, the incorporation of these Mexican territories led to significant problems, including the systematic dispossession of land from Mexicans and Mexican-Americans, and intensified the debates over slavery in the United States.
Racial Considerations and Pragmatism
Racism played a part in the U.S. decision not to pursue the annexation of all Mexico, as many Americans held derogatory views towards people of mixed ancestry, considering them as "mongrels." Moreover, taking all of Mexico was seen as a potential source of expensive and complicated problems. Instead, the focus was on acquiring the California and New Mexico territories, which increased U.S. territory substantially while avoiding the complexities of governing a large, diverse population and maintaining internal stability.
Consequences of Territorial Expansion
The aftermath of territorial acquisition from Mexico set a pattern of violence and racial antagonism that resonates to this day. Legal challenges and discriminatory practices led to the loss of lands owned by tejanos, californios, and other Mexican populations in the new American territories, perpetuating cycles of inequality and conflict.