Final answer:
James K. Polk was the President during the Mexican war and played a significant role in its outbreak and military strategy.
Step-by-step explanation:
The word of the President during the Mexican War was James K. Polk. President Polk played a significant role in the outbreak of the Mexican-American War in 1846. He saw an opportunity to acquire more territory for the United States and deliberately heightened tensions with Mexico, leading to clashes and eventually war. Polk's administration declared war on Mexico, and he was responsible for commanding U.S. forces and formulating military strategy during the war.
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