President Polk Declares War
On May 11, 1846 (166 years ago today) President James K. Polk asked Congress for a Declaration of War against Mexico, beginning the Mexican-American War.
On a push from outgoing President John Tyler and a lame duck congress, Texas joined the U.S. as a state in early 1845. When this happened, the Mexican government broke off diplomatic relations with the U.S. The border of Texas as an independent state had never been settled. The Republic of Texas claimed land up to the Rio Grande based on the Treaties of Velasco. Mexico refused to accept these as valid, claiming the border as the Nueces River. Congress' annexation resolution was silent as to what the border actually was and this helped secure passage of the motion to make Texas a state.
President Polk came into office and claimed the Rio Grande as the correct boundary. This provoked a dispute with Mexico. In June 1845, Polk sent General (and future President) Zachary Taylor to Texas, and by October 3rd, 500 American troops were on the Nueces River, prepared to defend Texas from a Mexican invasion.
Polk had instructed the Pacific Squadron to seize the California ports if Mexico declared war while staying on good terms with the inhabitants. But to end another threat of war with Britain over Oregon Country, Polk signed the Oregon Treaty dividing the territory. This angered northern Democrats who felt Polk was preferring southern expansion over northern expansion.
On November 10, 1845, Polk sent John Slidell, a secret representative, to Mexico City with an offer of $25 million ($671,538,462 in today's dollars) for the Rio Grande border in Texas and Mexico’s provinces of Alta California and Santa Fe de Nuevo México. U.S. expansionists wanted California to thwart British ambitions in the area and to gain a port on the Pacific Ocean. Polk authorized Slidell to forgive the $3 million ($81 million adjusted for inflation today) owed to U.S. citizens for damages caused by the Mexican War of Independence and pay another $25 to $30 million ($672 million to $806 million today) in exchange for the two territories. Mexico was not inclined nor able to negotiate. In 1846 alone, the presidency of Mexico changed hands four times. Mexican public opinion was firmly against selling the territories to the United States. When Mexican President Jose Joaquin de Herrera considered meeting with Slidell to settle the problem of Texas annexation peacefully, he was accused of treason and deposed. After a more nationalistic government under General Mariano Paredes y Arrillaga came to power, it publicly reaffirmed Mexico's claim to Texas and Slidell returned home.
President Polk ordered General Taylor and his forces south to the Rio Grande, entering the territory that Mexicans disputed. Taylor ignored Mexican demands to withdraw to the Nueces and constructed a makeshift fort (later known as Fort Brown) on the banks of the Rio Grande opposite the city of Matamoros, Tamaulipas. On April 25, 1846, a 2,000-strong Mexican cavalry detachment attacked a 70-man U.S. patrol, killing 16 U.S. soldiers.
Polk received word of this and he considered it to be a "casus belli" (cause for war). His message to Congress on May 11, 1846 stated that "Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon American soil." Congress approved the declaration of war on May 13, with southern Democrats in strong support. Sixty-seven Whigs voted against the war on a key slavery amendment, but on the final passage only 14 Whigs voted no, including Rep. John Quincy Adams (an probably Congressman Abraham Lincoln, who later challenged Polk on his casus belli.) Congress declared war on Mexico on May 13, 1846 after only a few hours of debate.
On a push from outgoing President John Tyler and a lame duck congress, Texas joined the U.S. as a state in early 1845. When this happened, the Mexican government broke off diplomatic relations with the U.S. The border of Texas as an independent state had never been settled. The Republic of Texas claimed land up to the Rio Grande based on the Treaties of Velasco. Mexico refused to accept these as valid, claiming the border as the Nueces River. Congress' annexation resolution was silent as to what the border actually was and this helped secure passage of the motion to make Texas a state.
President Polk came into office and claimed the Rio Grande as the correct boundary. This provoked a dispute with Mexico. In June 1845, Polk sent General (and future President) Zachary Taylor to Texas, and by October 3rd, 500 American troops were on the Nueces River, prepared to defend Texas from a Mexican invasion.
Polk had instructed the Pacific Squadron to seize the California ports if Mexico declared war while staying on good terms with the inhabitants. But to end another threat of war with Britain over Oregon Country, Polk signed the Oregon Treaty dividing the territory. This angered northern Democrats who felt Polk was preferring southern expansion over northern expansion.
On November 10, 1845, Polk sent John Slidell, a secret representative, to Mexico City with an offer of $25 million ($671,538,462 in today's dollars) for the Rio Grande border in Texas and Mexico’s provinces of Alta California and Santa Fe de Nuevo México. U.S. expansionists wanted California to thwart British ambitions in the area and to gain a port on the Pacific Ocean. Polk authorized Slidell to forgive the $3 million ($81 million adjusted for inflation today) owed to U.S. citizens for damages caused by the Mexican War of Independence and pay another $25 to $30 million ($672 million to $806 million today) in exchange for the two territories. Mexico was not inclined nor able to negotiate. In 1846 alone, the presidency of Mexico changed hands four times. Mexican public opinion was firmly against selling the territories to the United States. When Mexican President Jose Joaquin de Herrera considered meeting with Slidell to settle the problem of Texas annexation peacefully, he was accused of treason and deposed. After a more nationalistic government under General Mariano Paredes y Arrillaga came to power, it publicly reaffirmed Mexico's claim to Texas and Slidell returned home.
President Polk ordered General Taylor and his forces south to the Rio Grande, entering the territory that Mexicans disputed. Taylor ignored Mexican demands to withdraw to the Nueces and constructed a makeshift fort (later known as Fort Brown) on the banks of the Rio Grande opposite the city of Matamoros, Tamaulipas. On April 25, 1846, a 2,000-strong Mexican cavalry detachment attacked a 70-man U.S. patrol, killing 16 U.S. soldiers.
Polk received word of this and he considered it to be a "casus belli" (cause for war). His message to Congress on May 11, 1846 stated that "Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon American soil." Congress approved the declaration of war on May 13, with southern Democrats in strong support. Sixty-seven Whigs voted against the war on a key slavery amendment, but on the final passage only 14 Whigs voted no, including Rep. John Quincy Adams (an probably Congressman Abraham Lincoln, who later challenged Polk on his casus belli.) Congress declared war on Mexico on May 13, 1846 after only a few hours of debate.