Final answer:
The Mexican-American War was caused by Manifest Destiny, the desire for slaveholding states, and the Texas Revolution.
Step-by-step explanation:
The Mexican-American War was primarily caused by multiple factors: Manifest Destiny, the desire to form slaveholding states, and the Texas Revolution. Manifest Destiny was the belief that it was the divine right and duty of the United States to expand westward across the North American continent. This idea fueled territorial ambitions and led to conflict with Mexico. The desire for slaveholding states also played a role, as the issue of slavery further intensified tensions between the two nations. Finally, the Texas Revolution and the annexation of Texas by the United States placed the two countries on a collision course, ultimately triggering the war.
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