“I do not think there was ever a more wicked war than that waged by the United States on Mexico,” said Ulysses S. Grant in 1879, more than thirty years after he had fought in that war as a young lieutenant. As he was dying of cancer in 1885, Grant re- asserted that the American war against Mexico was “one of the most unjust ever waged by a stronger against a weaker nation.” Like the adventure in Iraq more than a century later, it was a war of choice, not of necessity, a war of aggression that expanded the size of the United States by nearly one quarter and reduced that of Mexico by half. And in a glaring example of unintended consequences, the issue of slavery in this new American territory set in motion a series of events that would produce a much bigger war fifteen years later that nearly tore apart the United States.
Two principal forces impelled Americans toward what historian Amy Greenberg as well as General Grant consider a wicked war. The first was the annexation of Texas in 1845. Soon after Mexico won its independence from Spain in 1821, the new government offered American settlers large land grants to move into its sparsely populated northern province of Tejas. The Mexican government soon had reason to regret this policy. The Americans brought slaves in defiance of a Mexican law abolishing the institution. They also defied Mexican efforts to regulate land claims and political activities.
Despite Mexican attempts to ban further immigration, by 1835 30,000 Americans lived in Texas, where they outnumbered native Mexicans (tejanos) by six to one. Determined to establish their own government, the American Texans met at a village appropriately named Washington in 1836 and declared their independence. After suffering the slaughter of all 187 defenders of the mission in San Antonio called the Alamo and another massacre of more than three hundred captives at the city of Goliad, the Texans defeated a larger Mexican army at San Jacinto on April 21, 1836. The Texans captured the Mexican commander Antonio López de Santa Anna and forced him to sign a treaty recognizing the independent republic of Texas.
Although the Mexican Congress repudiated this treaty, the Texans managed to maintain their independence for almost a decade even as they petitioned repeatedly for annexation by the United States. These petitions, however, ran into a snag in Washington, where the growing controversy over the extension of slavery temporarily derailed the drive for annexation. So did the opposition of most Whigs to the idea of continual territorial expansion, which was embraced by the “Young America” faction that increasingly dominated the Democratic Party and generated the second impulse toward the Mexican War. The “Manifest Destiny” of the United States was to possess the whole of North America, proclaimed John L. O’Sullivan of The Democratic Review in 1845. “Yes, more, more, more!…till our national destiny is fulfilled and…the whole boundless continent is ours.”1
Set against this demand for expansion of territory was the Whig philosophy of “internal improvements” by building up the infrastructure of transportation, education, and economic development within the existing borders of the United States. “Opposed to the instinct of boundless acquisition stands that of Internal Improvement,” wrote the Whig journalist Horace Greeley. “A nation cannot simultaneously devote its energies to the absorption of others’ territories and improvement of its own.”2
The foremost exponent of this Whig position was Henry Clay, a three-time loser as a presidential candidate who nevertheless was an immensely influential political figure in the first half of the nineteenth century. His third try for the nation’s highest office came in 1844, when he was defeated by the crosscurrents of Manifest Destiny and the antislavery opposition to the annexation of Texas. Clay’s presumptive Democratic opponent in this election was Martin Van Buren, also making his third bid for the presidency after winning in 1836 and losing four years later. Both Clay and Van Buren came out against annexation of Texas in letters published simultaneously on April 27, 1844. As matters turned out, however, these letters sealed their fate. The pro-annexation current ran so strongly in the Democratic Party that it nominated the dark-horse candidate James K. Polk of Tennessee on a platform that endorsed the acquisition not only of Texas but also of the Oregon Territory through Canada up to the border of Russian Alaska above the 54th parallel.
Despite the slogan “Fifty-four forty or fight!” that seemingly courted war with Britain over possession of British Columbia, it was the Texas issue that caught fire with the electorate. Annexation sentiment was especially strong in the South, which welcomed the prospect of a huge new slave state. To stem the stampede of many Southern Whigs to Polk on this issue, Clay published two more letters in July explaining that while he still opposed annexation if it would mean war with Mexico, he would acquiesce if it could be accomplished without war and with consensus support of Americans. This waffling probably cost him the election. Enough antislavery Whig voters in New York abandoned Clay and cast their ballots for the tiny Liberty Party to give that state—and therefore the presidency—to Polk by a margin of five thousand votes.
Clay and Polk are two of the five principal leaders around whom Greenberg organizes her book. A sixth figure enters the story briefly: Polk’s wife Sarah, a politically savvy woman who became his alter ego. “Were it not for her political skills, James Polk might never have won office,” writes Greenberg with perhaps a touch of hyperbole. “Members of both parties knew that Polk’s election would be a two-for-one…. Together they made, if not a good president, certainly a successful one.”
Polk’s success consisted mainly in presiding over the acquisition of more territory than any other president. He moved quickly to complete the annexation of Texas, which came in as the twenty-eighth state (and fifteenth slave state) in 1845. Polk then compromised with Britain to establish the northern border of the Oregon Territory at the 49th parallel. Having pledged to fight for a border of fifty-four forty, Polk angered many Northern Democrats with his refusal to risk war with Britain while being willing to provoke war with Mexico by annexing Texas and insisting on a border at the Rio Grande River instead of the old Mexican border at the Nueces River, which effectively doubled the size of Texas now claimed by the United States.
The new president sent an envoy to Mexico City to try to intimidate the unstable government into accepting the Rio Grande border and selling New Mexico and California to the United States. Meeting refusal, Polk ordered General Zachary Taylor to lead a contingent of American soldiers (which included Lieutenant Ulysses S. Grant) to the Rio Grande. Polk hoped this move would provoke an incident that would enable the United States to declare war and seize the territory that Mexico refused to sell. If not, Polk intended to ask Congress for a declaration of war anyway. In the event, the Mexican commander on the south bank of the Rio Grande created an incident by sending troops across the river to attack an American patrol, killing eleven of them.
Even before this news reached Washington on May 9, Polk’s cabinet had decided to request a declaration of war. Now the president had his casus belli. He sent a message to Congress asking not for a declaration of war as such, but for a resolution asserting that war already existed because Mexico “has invaded our territory and shed American blood upon the American soil.” As Greenberg notes, “None of it was true—but Polk didn’t consider it lies.” He believed that “a greater truth” was at stake: “As war exists, and notwithstanding all our efforts to avoid it, exists by the act of Mexico herself, we are called upon by every consideration of duty and patriotism to vindicate with decision the honor, the rights, and the interest of our country.”
Most Democrats were enthusiastic proponents of this war; most Whigs were opposed, branding it “Mr. Polk’s War.” (Greenberg prefers to call it “Mr. and Mrs. Polk’s War,” the title of Part Two of her book.) Congressional Democrats attached the declaration that war existed by the act of Mexico as a preamble to a bill to authorize funds and supplies for American soldiers who were now in harm’s way. This was a cynical ploy to force Whigs to vote yes or be forever tainted by a refusal to support the troops. It worked. Only two Whigs in the Senate and fourteen in the House (including former president John Quincy Adams) voted against the declaration.
For the same reason that most Whig congressmen felt compelled to vote yes, many other Whigs volunteered to fight in a war they deplored in order to prove their patriotism. Two of the most prominent were Henry Clay Jr. and John J. Hardin (a colleague of Abraham Lincoln in Illinois Whig politics who preceded Lincoln as a congressman from the Springfield district). Clay and Hardin became colonels respectively of Kentucky and Illinois regiments. Hardin is the third of Greenberg’s main characters, a charismatic politician who believed in Manifest Destiny despite his Whig allegiance. When war came in 1846, he was the first man from Illinois to enlist. Henry Clay Jr. was considerably less enthusiastic but no less determined. His departure from home and family was poignant and painful. “How bitter it was,” writes Greenberg, “that Henry Junior was risking death for a president his father detested and a conflict he despised.”
Death came to both Clay and Hardin at the Battle of Buena Vista in northern Mexico in February 1847. This battle was the most remarkable of American victories in the war, fought against odds of more than three to one. American armies had a long string of military successes that gave the United States control of New Mexico and California, and they captured Mexico City itself by September 1847. Nevertheless, the growing list of casualties and reports of atrocities by American soldiers against Mexican civilians and of savage attacks by Mexican rancheros (guerrillas) on American soldiers intensified antiwar sentiment in the United States. Total American deaths of 13,283 (seven eighths of them from disease) represented 17 percent of all American soldiers, the highest rate for any war except the Civil War. Poorly disciplined volunteer soldiers occupying Mexican cities “committed atrocities against Mexican civilians that would come to shock Americans back home,” Greenberg writes. Lieutenant Grant wrote to his fiancée Julia Dent from Monterrey:
Some of the volunteers and about all of the Texans seem to think it perfectly right…to murder them where the act can be covered by the dark…. I would not pretend to guess the number of murders that have been committed upon the persons of poor Mexicans and the soldiers, since we have been here, but the number would startle you.
1 Frederick Merk, Manifest Destiny and Mission in American History: A Reinterpretation (Knopf, 1963), p. 52. ↩
2 Horace Greeley, Why I Am a Whig (New York, 1851), p. 6. ↩