The U.S.-Mexican War (1846-1848) had significant effects on Mexico, particularly through the signing of the Treaty of Guadalupe Hidalgo. This treaty resulted in Mexico ceding over 500,000 square miles of territory to the United States, which included present-day California, Arizona, New Mexico, Nevada, Utah, and parts of Colorado and Wyoming.
The territorial loss had profound implications for Mexico, leading to economic challenges, a sense of national humiliation, and increased instability. The war drained Mexican resources and contributed to political and social strife in the country following the conflict.
Therefore, the most accurate statement regarding the impact of the U.S.-Mexican War on Mexico is: It led to the Treaty of Guadalupe Hidalgo, which took over 500,000 square miles of territory from Mexico.