Introduction

In the early nineteenth century, many “second sons” of slave-holding families (who would not inherit the family plantations) moved west into the Mexican state of Texas, where land was plentiful and well suited for many of the same cash crops as were grown in other parts of the American South. Although these settlers were at first welcomed by the Mexican government, when the country abolished slavery in 1829, they instigated an independence movement that quickly escalated into a war. In 1836, after the Battle of San Jacinto, Mexico recognized Texas as an independent republic; yet tensions remained between the two nations over the disputed territory between the Nueces River and the Rio Grande, some 150 miles to the south.

When the United States agreed to the annexation of Texas in 1845, it also adopted the Rio Grande as the border, leading to a break in diplomatic relations with Mexico and, eventually, to Democratic President James K. Polk’s request for a war declaration in 1847. Polk asserted that the Mexican army had attacked on American soil; skeptical Whigs, including the freshman congressman from Illinois, Abraham Lincoln, questioned the veracity of Polk’s claim. Lincoln and his political compatriots accused Polk of illegitimately escalating a conflict over disputed territory for the sole purpose of extending slave territory. Indeed, Lincoln presented a series of resolutions on the floor of Congress, challenging Polk to identify the very spot where the alleged Mexican attack had occurred and to prove that it was, in fact, on America soil. The “spot resolutions,” as they became known, showcase Lincoln’s famous wit, but with a degree of acerbity that ultimately proved fatal to Lincoln’s career in the House, as Democrats charged him with being unpatriotic, unsupportive of the Army, and even disloyal.

Lincoln’s senior colleague, Henry Clay, also opposed the war publicly, but since his son fought and died in the battle of Vera Cruz, the Democratic press regularly portrayed Clay as two-faced and his opposition as insincere and politically motivated. In “The Great Speech of Clay,” one political cartoon with this trope, Clay’s anti-war audience (to the right) includes Horace Greeley, editor of the New York Tribune, who compares the position of anti-war Whigs with that of the New England Federalists who organized the Hartford Convention. This trope was taken up by at least one member of Congress in a speech haranguing his fellow legislators for their faithlessness to the war effort they had voted to commence only a short time before.

Not all opposition to the war was politically motivated, however: many Northern religious leaders, some of whom were pacifists on principle and some of whom were ardent anti-slavery advocates, freely denounced the war as an act of imperialism and a blatant attempt to increase the territory available to Southern slaveholders. Interestingly, Ulysses S. Grant’s account of the mindset of the troops on the ground in Texas during the conflict supports the latter interpretation (although it is worth noting that the date of Grant’s memoir is significantly after the fact).


Printed Resolution and Preamble on Mexican War: “Spot Resolutions,” Abraham Lincoln Papers: Series 1, General Correspondence, 1833 to 1916, December 22, 1847. Manuscript/Mixed Material. Library of Congress, https://goo.gl/oFoVkv.


Mr. LINCOLN moved the following preamble and resolutions, which were read and laid over under the rule:

Whereas the President of the United States, in his message of May 11, 1846, has declared that “the Mexican Government not only refused to receive him, [the envoy of the United States,] or listen to his propositions, but after a long-continued series of menaces, have at last invaded our territory and shed the blood of our fellow-citizens on our own soil.”

And again, in his message of December 8, 1846, that “we had ample cause of war against Mexico long before the breaking out of hostilities; but even then we forbore to take redress into our own hands until Mexico herself became the aggressor, by invading our soil in hostile array and shedding the blood of our citizens.”

And yet again, in his message of December 7, 1847, that the Mexican Government refused even to hear the terms of adjustment which he [our minister of peace] was authorized to propose, and finally, under wholly unjustifiable pretexts, involved the two countries in war, by invading the territory of the State of Texas, striking the first blow, and shedding the blood of our citizens on our own soil.” And whereas this House is desirous to obtain a full knowledge of all the facts which go to establish whether the particular spot on which the blood of our citizens was so shed was or was not at that time our own soil: Therefore, Resolved by the House of Representatives, That the President of the United States be respectfully requested to inform this House –

1st. Whether the spot on which the blood of our citizens was shed, as in his messages declared, was or was not within the territory of Spain, at least after the treaty of 1819 until the Mexican revolution.

2d. Whether that spot is or is not within the territory which was wrested from Spain by the revolutionary Government of Mexico.

3d. Whether that spot is or is not within a settlement of people, which settlement has existed ever since long before the Texas revolution, and until its inhabitants fled before the approach of the United States army.

4th. Whether that settlement is or is not isolated from any and all other settlements by the Gulf and the Rio Grande on the south and west, and by wide uninhabited regions on the north and east.

5th. Whether the people of that settlement, or a majority of them, or any of them, have ever submitted themselves to the government or laws of Texas or of the United States, by consent or by compulsion, either by accepting office, or voting at elections, or paying tax, or serving on juries, or having process served upon them, or in any other way.

6th. Whether the people of that settlement did or did not flee from the approach of the United States army, leaving unprotected their homes and their growing crops, before the blood was shed, as in the messages stated; and whether the first blood, so shed, was or was not shed within the enclosure of one of the people who had thus fled from it.

7th. Whether our citizens, whose blood was shed, as in his messages declared, were or were not, at that time, armed officers and soldiers, sent into that settlement by the military orders of the President, through the Secretary of War.

8th. Whether the military force of the United States was or was not so sent into that settlement after Gen. Taylor had more than once intimated to the War Department that, in his opinion, no such movement was necessary to the defence or protection of Texas.

Study Questions

A. What, exactly, does James K. Polk accuse Mexico of doing in his request for a declaration of war? Why do you think Abraham Lincoln was skeptical of these claims? Would the war seem more or less just depending upon the answers to the questions posed in the spot resolutions? Having once voted to authorize a declaration of war, are congressmen morally obligated, as Andrew Kennedy suggests, to see the thing through to the end, even if they come to see the war as unjust? Was the war with Mexico a legitimate war to protect American territory, or an illegitimate attempt to use federal power to protect and promote the expansion of slavery? Does Ulysses S. Grant’s account seem trustworthy as a reflection of the mindset of the troops on their mission at the time, or does it seem like an example of revisionist history, given his later experiences in the Civil War?

B. How might we connect the anti-war arguments presented here to the abolitionists’ denunciations of armed resistance?

C. In what ways do the arguments for and against the Mexican-American War compare with the arguments for and against the Spanish-American War?