In the White House now was James Polk, a Democrat, an expansionist, who, on the night of his inauguration, confided to his secretary of the navy that one of his main objectives was the acquisition of California. His order to General Taylor to move troops to the Rio Grande was a challenge to the Mexicans. It was not at all clear that the Rio Grande was the southern boundary of Texas, although Texas had forced the defeated Mexican general Santa Anna to say so when he was a prisoner. The traditional border between Texas and Mexico had been the Nueces River, about 150 miles to the north, and both Mexico and the United States had recognized that as the border. However, Polk, encouraging the Texans to accept annexation, had assured them he would uphold their claims to the Rio Grande.
Ordering troops to the Rio Grande, into territory inhabited by Mexicans, was clearly a provocation. Taylor’s army marched in parallel columns across the open prairie, scouts far ahead and on the flanks, a train of supplies following. Then, along a narrow road, through a belt of thick chaparral, they arrived, March 28, 1846, in cultivated fields and thatched-roof huts hurriedly abandoned by the Mexican occupants, who had fled across the river to the city of Matamoros. Taylor set up camp, began construction of a fort, and implanted his cannons facing the white houses of Matamoros, whose inhabitants stared curiously at the sight of an army on the banks of a quiet river.
The Washington Union, a newspaper expressing the position of President Polk and the Democratic party, had spoken early in 1845 on the meaning of Texas annexation: “Let the great measure of annexation be accomplished, and with it the questions of boundary and claims. For who can arrest the torrent that will pour onward to the West? The road to California will be open to us. Who will stay the march of our western people?”
It was shortly after that, in the summer of 1845, that John O’Sullivan, editor of the Democratic Review, used the phrase that became famous, saying it was “Our manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions.” Yes, manifest destiny.
All that was needed in the spring of 1846 was a military incident to begin the war that Polk wanted. It came in April, when General Taylor’s quartermaster, Colonel Cross, while riding up the Rio Grande, disappeared. His body was found eleven days later, his skull smashed by a heavy blow. It was assumed he had been killed by Mexican guerrillas crossing the river.
The next day (April 25), a patrol of Taylor’s soldiers was surrounded and attacked by Mexicans, and wiped out: sixteen dead, others wounded, the rest captured. Taylor sent a dispatch to Polk: “Hostilities may now be considered as commenced.”
The Mexicans had fired the first shot. But they had done what the American government wanted, according to Colonel Hitchcock, who wrote in his diary, even before those first incidents:
I have said from the first that the United States are the aggressors.… We have not one particle of right to be here.… It looks as if the government sent a small force on purpose to bring on a war, so as to have a pretext for taking California and as much of this country as it chooses.… My heart is not in this business…but, as a military man, I am bound to execute orders.
On May 9, before news of any battles, Polk was suggesting to his cabinet a declaration of war. Polk recorded in his diary what he said to the cabinet meeting:
I stated…that up to this time, as we knew, we had heard of no open act of aggression by the Mexican army, but that the danger was imminent that such acts would be committed. I said that in my opinion we had ample cause of war, and that it was impossible…that I could remain silent much longer…that the country was excited and impatient on the subj ect.…
The country was not “excited and impatient.” But the president was. When the dispatches arrived from General Taylor telling of casualties from the Mexican attack, Polk summoned the cabinet to hear the news, and they unanimously agreed he should ask for a declaration of war. Polk’s message to Congress was indignant: “Mexico has passed the boundary of the United States, has invaded our territory and shed American blood upon the American soil.…”
Congress then rushed to approve the war message. The bundles of official documents accompanying the war message, supposed to be evidence for Polk’s statement, were not examined, but were tabled immediately by the House. Debate on the bill providing volunteers and money for the war was limited to two hours, and most of this was used up reading selected portions of the tabled documents, so that barely half an hour was left for discussion of the issues.
The Whig party also wanted California, but preferred to do it without war. Nevertheless, they would not deny men and money for the operation and so joined Democrats in voting overwhelmingly for the war resolution, 174 to 14. In the Senate there was debate, but it was limited to one day, and the war measure passed, 40 to 2, Whigs joining Democrats. John Quincy Adams of Massachusetts, who originally voted with “the stubborn 14,” later voted for war appropriations.
Abraham Lincoln of Illinois was not yet in Congress when the war began, but after his election in 1846 he had occasion to vote and speak on the war. His “spot resolutions” became famous—he challenged Polk to specify the exact spot where American blood was shed “on the American soil.” But he would not try to end the war by stopping funds for men and supplies. Speaking in the House on July 27, 1848, he said:
If to say “the war was unnecessarily and unconstitutionally commenced by the President” be opposing the war, then the Whigs have very generally opposed it.… The marching an army into the midst of a peaceful Mexican settlement, frightening the inhabitants away, leaving their growing crops and other property to destruction, to you may appear a perfectly amiable, peaceful, unprovoking procedure; but it does not appear so to us.… But if, when the war had begun, and had become the cause of the country, the giving of our money and our blood, in common with yours, was support of the war, then it is not true that we have always opposed the war. With few individual exceptions, you have constantly had our votes here for all the necessary supplies.…
A handful of antislavery Congressmen voted against all war measures, seeing the Mexican campaign as a means of extending the southern slave territory. One of these was Joshua Giddings of Ohio, a fiery speaker, physically powerful, who called it “an aggressive, unholy, and unjust war.”
After Congress acted in May of 1846, there were rallies and demonstrations for the war in New York, Baltimore, Indianapolis, Philadelphia,and many other places. Thousands rushed to volunteer for the army. The poet Walt Whitman wrote in the Brooklyn Eagle in the early days of the war: “Yes: Mexico must be thoroughly chastised!… Let our arms now be carried with a spirit which shall teach the world that, while we are not forward for a quarrel, America knows how to crush, as well as how to expand!”
Accompanying all this aggressiveness was the idea that the United States would be giving the blessings of liberty and democracy to more people. This was intermingled with ideas of racial superiority, longings for the beautiful lands of New Mexico and California, and thoughts of commercial enterprise across the Pacific. The New York Herald said, in 1847: “The universal Yankee nation can regenerate and disenthrall the people of Mexico in a few years; and we believe it is a part of our destiny to civilize that beautiful country.”
The Congressional Globe of February 11, 1847, reported:
Mr. Giles, of Maryland—I take it for granted, that we shall gain territory, and must gain territory, before we shut the gates of the temple of Janus.… We must march from ocean to ocean.… We must march from Texas straight to the Pacific ocean, and be bounded only by its roaring wave.… It is the destiny of the white race, it is the destiny of the Anglo-Saxon race.…
The American Anti-Slavery Society, on the other hand, said the war was “waged solely for the detestable and horrible purpose of extending and perpetuating American slavery throughout the vast territory of Mexico.” A twenty-seven-year-old Boston poet and abolitionist, James Russell Lowell, began writing satirical poems in the Boston Couder (they were later collected as the Biglow Papers). In them, a New England farmer, Hosea Biglow, spoke, in his own dialect, on the war:
Ez fer war, I call it murder,—