I
THE APPROACH OF WAR

Upon the annexation of Texas (in 1845) Mexico at once severed her diplomatic relations with the United States. This result had been foreshadowed by the utterances of Mexican officials dating from the revival of the question in 1843. The relations, however, of the two countries had been difficult to adjust from the time when Mexico became independent in 1821. The most serious friction between them arose concerning four subjects: claims of the United States citizens on the government of Mexico; assistance given the Texans by the people of the United States; violation of Mexican territory by United States troops; and the annexation of Texas.

The immediate occasion, however, of the breach of diplomatic relations in 1845 was the annexation of Texas. When rumors of the renewal of the annexation movement came to the city of Mexico in the summer of 1843, President Santa Anna gave notice to the United States government, in a letter dated August 23d, from Secretary of State Bocanegra to Minister Waddy Thompson, that “the Mexican government will consider equivalent to a declaration of war against the Mexican Republic the passage of an act for the incorporation of Texas with the territory of the United States; the certainty of the fact being sufficient for the immediate proclamation of war, leaving to the civilized world to determine with regard to the justice of the cause of the Mexican Nation, in a struggle which it has been so far from provoking.”101

Thompson replied immediately with a sharply resentful letter, questioning the sources of information of the Mexican authorities as to the prospect of annexation, but refusing any explanation whatever. Another letter from Bocanegra to Thompson asserted that the advices of the Mexican government on the subject were official and reliable, and sought to justify the attitude of Mexico as follows: “but as it may happen that ambition and delusion may prevail over public propriety, that personal views may triumph over sane and just ideas, and that the vigorous reasoning of Mr. John Quincy Adams and his co-laborers may be ineffectual, how can it be considered strange and out of the way that Mexico, under such a supposition, should announce that she will regard the annexation of Texas as an act of declaration of war?”102 Secretary of State Upshur approved the course of Thompson, and instructed him that, in case he were again addressed in such offensive language, he should demand either a withdrawal of the letter or a suitable apology.

On November 3, 1843, Almonte, the Mexican minister at Washington, in accordance with the instructions of his government, notified Upshur, in a communication whose terms were hardly less offensive than those used by Bocanegra to Thompson, that if “the United States should, in defiance of good faith and of the principles of justice which they have constantly proclaimed, commit the unheard-of act of violence (inaudito atentado—the expression [says the official translator] is much stronger than the translation) of appropriating to themselves an integrant part of the Mexican territory, the undersigned, in the name of his Nation, and now for them, protests, in the most solemn manner, against such an aggression; and he moreover declares, by express order of his Government, that, on sanction being given by the Executive of the Union to the incorporation of Texas into the United States, he will consider his mission ended, seeing that, as the Secretary of State will have learned, the Mexican Government is resolved to declare war so soon as it receives information of such an act.” On November 8th Upshur replied, in a restrained and dignified way, repelling both the threats and insinuations of Almonte’s letter and intimating that the policy of the United States would not be affected by them.103 To this Almonte rejoined, on the 11th, suggesting that Upshur had been misled by an incorrect translation of the letter of November 3d, and disclaiming any intention to impute to the authorities of the American Union unworthy views or designs as to Texas. December 1, 1843, Upshur replied, denying that he had misunderstood Almonte, and declaring that the United States regarded Texas as an independent nation and did not feel called on to consult any other nation in dealing with it.104

On the accomplishment of annexation, the threat of Almonte was carried out. The joint resolution making the offer was approved March 1, 1845, and on March 6th he demanded his passports. March 28th the United States minister in Mexico was officially notified that the diplomatic intercourse between the two countries was at an end.105 The expressions of the Mexican papers indicated the most intense popular excitement in that country, and those of the government treated the war as already existing.106 Two decrees were passed by the Mexican congress and approved by President Herrera, one on June 4th and the other on June 7th, providing for an increase of the available force in order to resist annexation.107 July 20th the “supreme government,” or executive, recommended to the congress a declaration of war against the United States from the moment when the government should know that annexation had been effected or Texas had been invaded.

There can be little question, indeed, that impatience on both sides had gone beyond the point of safety and was threatening appeal to arms. No theory of a conspiracy is needed to explain the war with Mexico. While it was strongly opposed and condemned by a bold and outspoken minority, the votes in Congress and the utterances of the contemporaneous journals show that it was essentially a popular movement, both in Mexico and in the United States. The disagreement reached the verge of an outbreak in 1837, and the only thing that prevented a conflict then was that Congress was a bit more conservative than the President; but neither the aggressiveness of Jackson nor even that of Polk would have been so likely to end in actual fighting had it not been well understood that they were backed by sympathetic majorities. On the Mexican side, at the critical moment, the pacific tendencies of the executive were overpowered by the angry impulse of the people.

May 28, 1845, General Taylor, who was in command of the troops in the Southwest, was ordered, in view of the prospect of annexation, to hold himself in readiness to advance into Texas with the approval of the Texan authorities, and to defend that republic from any invasion of which he should be officially informed after Texas had consented to annexation on the terms offered. June 15th he was ordered to advance, with the western frontier of Texas for his ultimate destination. There he was to occupy a convenient point “on or near the Rio Grande,” but to limit himself to the defence of the territory of Texas unless Mexico should declare war against the United States. He was subsequently directed to protect the territory up to the Rio Grande, avoiding, however, except in case of an outbreak of hostilities, any attack on posts actually held by Mexicans, but placing at least a part of his forces west of the Nueces.108 In July, General Taylor advanced into Texas, and in August he established his camp on the west bank of the Nueces, near Corpus Christi.109 The spot which he selected could hardly be considered as “near” the Rio Grande, being, in fact, about one hundred and fifty miles therefrom. The location was chosen because of its convenience as a temporary base either for defensive or offensive operations.

The army remained in camp near Corpus Christi several months. The information Taylor obtained here and reported to Washington indicated no threatening movement on the part of the Mexicans; but on October 4th he suggested that, if the United States government meant to insist on the Rio Grande as the boundary, it would gain an advantage by occupying points on that river. He therefore suggested an advance to Point Isabel and Laredo.110 Meanwhile had come the attempt to renew diplomatic relations between the United States and Mexico, which ended in failure. January 13, 1846, when it was known in Washington that Slidell would probably not be received by the Mexican government, Taylor was ordered to advance to the Rio Grande.111

Up to the time of this movement the Mexican government had neglected the distinction in the validity of its claims to the territory east of the Rio Grande. It strenuously asserted the right of Mexico to the whole of Texas, whatever its limits might be, and declared that annexation would be tantamount to a declaration of war. From the Mexican point of view, Taylor invaded Mexico the moment he entered Texas. But when he advanced to the Rio Grande the distinction was finally made. April 12, 1846, he was warned by Ampudia, general in command of the Mexican forces at Matamoras, to retire in twenty-four hours—not beyond the Sabine, as one might have expected from the previous attitude of the Mexican government, but beyond the Nueces.112

A few days later occurred the first conflict. April 24th a party of dragoons sent out by Taylor was ambushed on the east side of the river by a large force of Mexicans, and after a skirmish, in which a number of men were killed and wounded, was captured.113 The official report of this affair reached Washington the evening of Saturday, May 9th.114 President Polk had already decided, in conformity with the judgment of all his cabinet except Bancroft, to send to Congress a message recommending a declaration of war. Now, in formulating the reasons for the declaration, he asserted that “Mexico has passed the boundary of the United States, has invaded our territory, and shed American blood upon the American soil,”115 and with the unanimous concurrence of his cabinet he sent the message to Congress, Monday, May 11th.

On the same day a bill providing for the enlistment of fifty thousand soldiers and the appropriation of ten million dollars, the preamble to which re-echoed the President’s assertion that war existed by the act of Mexico itself, passed the House by a vote of 174 to 14.116

II
CONQUERING A PEACE (1846–1848)

It was only after Polk felt assured of the refusal to receive Slidell117 that he assumed an attitude so aggressive as clearly to challenge war; and from that time forward it seems to have been his desire to carry the struggle just far enough to bring Mexico to the point of conceding a territorial indemnity on the terms which he had intended to offer through Slidell. In accordance with this policy he suggested, while the question of Slidell’s reception by the Paredes government was yet in suspense, that Slidell should be directed to go on board a United States vessel and wait for further instructions.118 The object of this plan was evidently to be able to resume negotiations, as soon as Mexico had felt the pressure sufficiently, without the delays incident to a correspondence between the two capitals. The same considerations influenced, at a later stage of the war, the appointment of Trist.119 To this method of pushing on the conflict, with the sword in one hand and the olive-branch in the other, Polk applied the peculiar designation of “conquering a peace.”

After the declaration of war by Congress, May 12, 1846, General Scott, the commander-in-chief of the United States Army, was appointed to command directly the forces that were to operate against Mexico. According to a plan of operations which appears to have originated with President Polk himself, but which was concurred in by Secretary of War Marcy and by General Scott, New Mexico and California, which Polk intended to claim by way of indemnity, and Chihuahua, were to be occupied and held; the United States forces were to be pushed toward the heart of Mexico in order to force the Mexicans to terms; and the naval forces in the Gulf and the Pacific were assigned specific duties in connection with the general scheme.120

The plan was in keeping with the main purpose of the war, and was, on the whole, well adapted to insure success. The northern provinces were far distant from the city of Mexico; the hold of the central government upon them was but slight; and, even if its available forces had been sufficiently strong and effective to send the troops needed to resist invasion, the difficulties of transportation would have been hard to overcome. Of course, similar difficulties were experienced in throwing the United States troops into the interior of northern Mexico; but such operations were far easier for a strong government with abundant resources than for one so ill established and so lacking in means as that of Herrera or Paredes. The population of the north Mexican provinces was sparse and unenergetic, and could not be relied on for its defence; the local governments were weak and inefficient; and in 1846 that of California was disastrously affected by dissensions between two rival leaders, JosÉ Castro and Pio Pico, representing respectively the northern district and the southern.121 It was in the northern district, in the lower valley of the Sacramento River and near the bay of San Francisco, that the foreign population, including the Americans, was most numerous.

The plan for a campaign directed at the city of Mexico was gradually developed as the war went on. The impression of Polk and his advisers at first was that a vigorous invasion of Mexico would end the war, without the necessity of pushing it far into the interior; and, since operations on the coast in the summer were so dangerous, the attack was made first in the north. The resistance of the Mexicans was, however, more desperate and prolonged than was expected, and ultimately the change was made to the shorter and more direct line of advance by way of Vera Cruz.

The occupation of New Mexico and California was accomplished speedily and with little resistance. General Kearny occupied New Mexico in the summer of 1846, and the occupation of California under Commodore R.F. Stockton was completed by January, 1847. The first expeditions against Mexico from the north under Wool and Doniphan were inconclusive.

The army which was most depended on to force Mexico to terms was that operating in the east. The campaign in this quarter began with an advance from Matamoras through Tamaulipas and Nuevo LeÓn into Coahuila. But as it progressed the plan was gradually assimilated, so far as these states were concerned, to that which had been followed in dealing with California and New Mexico, and became one of simple occupation; while the attack was shifted to the south, and the final advance was made from Vera Cruz direct on the city of Mexico.

In the prosecution of the war, in this part especially, the administration was much hampered by the character and conduct of the generals on whom the detailed development and execution of the plan devolved. The friction thus arising was increased by mutual suspicions of political motives between President Polk, certain members of his cabinet, and the generals themselves.

In this war the United States troops, though always outnumbered—in some cases heavily—and usually with the advantage of position against them, enjoyed such superiority both in morale and in matÉriel that they were almost uniformly victorious. Their victories, however, were by no means easy; on the contrary, they were obtained only at the cost of no little bloody fighting and of great loss of men. And, as is not unusual in like emergencies, there was much complaint of the extravagance and inefficiency of the quartermaster’s department.122 The attack on Mexico began with the advance of Taylor’s army. Two battles, Palo Alto, on May 8, 1846, and Resaca de la Palma, on the following day, were required to drive the Mexicans across the Rio Grande. Taylor then advanced from Matamoras through Tamaulipas into Nuevo LeÓn, and, after defeating the Mexicans in a three days’ battle, September 21–23, at Monterey, the capital of Nuevo LeÓn, he captured that city. Saltillo, the capital of Coahuila, was occupied by the United States troops on November 16th, and Victoria, the capital of Tamaulipas, December 29th.

It had long before this become a most important question whether the campaign should be confined to the occupation and cutting-off of northern Mexico, or whether the army should be pushed on toward the city of Mexico. Taylor recommended the first of these two plans; but when asked his advice as to what should be done further, and especially whether an expedition should be aimed at the city of Mexico from near Vera Cruz, he had been hesitating and non-committal in his answer.123 Orders issued direct from Washington, September 22, 1846, in connection with the scheme before it was fully developed, to General Patterson, one of Taylor’s subordinates, drew from Taylor himself a resentful protest.124 Finally the plan of capturing Vera Cruz and marching thence upon the city of Mexico was adopted by Polk and his cabinet, with a little objection from Buchanan as to advancing beyond Vera Cruz,125 and Scott was elected to lead the expedition. Soon after his appointment, he left Washington, and about the end of December he reached Matamoras and began to make preparations for the attack on Vera Cruz. Part of Taylor’s men were drawn away for the southern campaign, and renewed complaints from him were added to the general chorus of discord and dissatisfaction.126

Information of the shifting of the attack to the south reached Santa Anna through intercepted despatches, and he at once conceived the project of a counter-stroke. Advancing northward with an army of more than twenty thousand men, he came upon Taylor February 23, 1847, with only about one-fourth that number at Buena Vista, a few miles south of Saltillo. The American troops gained a brilliant victory,127 and with this the serious work of the “army of occupation” was at an end.

Attention was now centred on the southern campaign. During the month of February, 1847, Scott’s troops were conveyed by sea from Brazos Santiago and concentrated on the island of Lobos, about sixty miles south of Tampico. On March 9th a landing was made without opposition near Vera Cruz. With the co-operation of the naval forces under Commodore Conner the city was invested, and, after a brief siege culminating in a sharp bombardment, was captured, March 29, 1847.128

Next in order was the advance upon the city of Mexico, which began April 8th. The first resistance was met at Cerro Gordo, where, on April 17th and 18th, Scott’s army of not more than nine thousand drove thirteen thousand Mexicans, in disastrous defeat, from a naturally strong and well-fortified position. Finally there was a series of battles near the city of Mexico, which culminated in its capture, and which will be referred to further on.

Meanwhile another effort was made by Polk to negotiate, an idea which even after the failure of the Slidell mission had been kept steadily in view.

In answer to the proposition to negotiate which came through Trist, the American commissioner, Santa Anna contrived to intimate that, if he were paid ten thousand dollars down and one million on the conclusion of peace, negotiations should begin at once. After consulting with several of his officers, in a conference held late in July or early in August, Scott paid the ten thousand dollars.129 Still no step was taken by the Mexicans toward negotiation until they were beaten in the engagements at Contreras, August 19th and 20th, and Churubusco, August 20, 1847. Then Scott himself proposed an armistice, which was accepted August 24th. Commissioners were appointed to meet Trist, and the effort to conclude a treaty began. Whether it could have been accomplished at that stage of the “conquering” on the basis of his instructions is uncertain; but Trist’s wavering attitude undoubtedly served to make the possibility much less. The Mexican commissioners still refused to come to terms, and submitted counter-propositions which were in conflict with those instructions, but which Trist referred to the authorities at Washington.130 As soon as unofficial news of what Trist had done was received there, President Polk, without waiting to hear from him directly, ordered his recall.131

In the mean time the armistice had been terminated and the advance of the United States troops renewed. The victories of Molino del Rey, September 8th, and Chapultepec, September 13th, opened the way to the city of Mexico, which was occupied on September 14th.132 Santa Anna abdicated, and on November 22d the new government announced to Trist that it had appointed commissioners to negotiate. Trist had already received the letter recalling him; but, in spite of this fact, he listened to the suggestion of the Mexicans that they were not officially notified of his recall, and were anxious to negotiate on the terms of his original instructions.

The negotiations terminated with the treaty of Guadalupe-Hidalgo, signed February 2, 1848. The boundary agreed upon was to follow the Rio Grande from its mouth to the line of New Mexico; that line westward and northward to the first branch of the Gila it should cross; that branch and the Gila to the Colorado; and the line between Upper and Lower California thence to the Pacific.133 For the territory thus ceded by Mexico the United States was to satisfy the claims of its citizens on the Mexican government, and to pay in addition thereto fifteen million dollars. In spite of the fact that Trist’s authority had been withdrawn before the final negotiations, President Polk submitted the treaty to the Senate, and after some opposition and suspense it was ratified, March 10, 1848, by a vote of 38 to 14.