The History of American Military. Richard W. Stewart
victory at Churubusco brought an offer from Santa Anna to reopen negotiations. Scott proposed a short armistice, and Santa Anna quickly agreed. For two weeks Trist and representatives of the Mexican government discussed terms until it became clear that the Mexicans would not accept what Trist had to offer and were merely using the armistice as a breathing spell. On September 6 Scott halted the discussions and prepared to assault Mexico City.
Though refreshed by two weeks of rest, his forces now numbered only about 8,000. Santa Anna was reputed to have more than 15,000 and had taken advantage of the respite to strengthen the defenses of the city. And ahead on a high hill above the plain was the Castle of Chapultepec guarding the western approaches.
Scott’s first objective, about half a mile west of Chapultepec, was a range of low stone buildings, containing a cannon foundry, known as El Molino del Rey. It was seized on September 8, though at heavy cost from unexpected resistance. At eight o’clock on the morning of September 13, after a barrage from the 24-lb. guns, Scott launched a three-pronged attack over the causeways leading to Chapultepec and up the rugged slopes. Against a hail of Mexican projectiles from above, his determined troops rapidly gained the summit, though they were delayed at the moat waiting for scaling ladders to come up. By half past nine o’clock the Americans were overrunning the castle despite a valiant but doomed defense by brave young Mexican cadets. Scarcely pausing, they pressed on to Mexico City by the two routes available and by nightfall held two gates to the city. Exhausted and depleted by the 800 casualties suffered that day, the troops still had to face house-to-house fighting; but at dawn the next day, September 14, the city surrendered.
Throughout the campaign from Vera Cruz to Mexico City, General Scott had displayed not only dauntless personal courage and fine qualities of leadership but great skill in applying the principles of war. In preparing for battle he would order his engineers to make a thorough reconnaissance of the enemy’s position and the surrounding terrain. He was thus able to execute brilliant flanking movements over terrain that the enemy had considered impassable, notably at Cerro Gordo and the Pedregal, the latter a fine illustration of the principle of surprise. Scott also knew when to violate the principles of warfare, as he had done at Puebla when he deliberately severed his line of communications. Able to think beyond mere tactical maneuver, Scott was perhaps the finest strategic thinker in the American Army in the first half of the nineteenth century.
“He sees everything and counts the cost of every measure,” said Captain Lee. Scott for his part ascribed his quick victory over Mexico, won without the loss of any battle, to the West Pointers in his army, Lee, Grant, and many others. As for the troops, the trained and disciplined regulars had come off somewhat better than the volunteers; but all the army on the whole had fought well. Scott had seen to it that the men fought at the right time and place. Grant summed it up: “Credit is due to the troops engaged, it is true, but the plans and strategy were the general’s.”
Occupation and Negotiation in Mexico City
For two months the only responsible administration in Mexico was the American military government under Scott. The collection of revenues, suppression of disorder, administration of justice, all the details of governing the country were in the hands of the Army. It has been said that some Mexicans believed that Scott’s administration of their city was more efficient and respectful of Mexican property than their own government’s. It was an instructive lesson in the value of a careful and relatively enlightened occupation policy. When the Mexicans finally organized a government with which Commissioner Trist could negotiate a peace treaty, dispatches arrived from Washington instructing Trist to return to the United States and ordering Scott to resume the war. Knowing that the Mexicans were now sincerely desirous of ending the war and realizing that the government in Washington was unaware of the situation, both Trist and Scott decided to continue the negotiations.
On February 2, 1848, the Treaty of Guadalupe Hidalgo was signed. The U.S. Senate ratified it on March 10, but powerful opposition developed in Mexico. Not until May 30 were ratifications exchanged by the two governments. Preparations began immediately to evacuate American troops from Mexico. On June 12 the occupation troops marched out of Mexico City; on August 1, 1848, the last American soldiers stepped aboard their transports at Vera Cruz and quitted Mexican soil.
By the Treaty of Guadalupe Hidalgo the United States agreed to pay Mexico $15 million and to assume the unpaid claims by Americans against Mexico. In return, Mexico recognized the Rio Grande as the boundary of Texas and ceded New Mexico (including the present states of Arizona, New Mexico, Utah, and Nevada, a small corner of present-day Wyoming, and the western and southern portions of Colorado) and Upper California (the present state of California) to the United States. Mexico lost almost half of its land area to the United States by the terms of the treaty.
The Army on the New Frontier
The victory over Mexico, as well as the settlement of the Oregon boundary frontier in June 1846, added to the United States a vast territory that was to occupy the Army almost exclusively in the postwar years. For generations, the Army was to be the only force for law and order throughout thousands of square miles. First, the Army needed to explore this vast new conquest. In this task the Corps of Topographical Engineers played the leading role. Some knowledge of the new region had been gained by expeditions such as those of Capt. Benjamin L. E. Bonneville, Kearny, and 2d Lt. John C. Fremont; more had been gained during the Mexican War by “topogs” attached to Kearny’s march to California and Wool’s to Saltillo and after the war by Maj. William H. Emory’s work with the Mexican Boundary Commission. But much still remained to be done.
The most significant and far-reaching explorations were those to locate routes for transcontinental railroads. The first effort was directed toward the southwest, seeking an “ice-free, mountain-free” route. In that area, the necessity for defense against Comanches, Apaches, and Navahos meant that most of the Army had to be stationed between San Antonio and Fort Yuma. Forts had to be constructed, roads built, rivers sought as avenues of supply, and Indian trails mapped. In 1853 Congress authorized similar explorations on a northern route to the Pacific from Chicago and a central route from St. Louis.
Railroad construction did not begin until after the Civil War. Emigrants setting out for the West, in increasing numbers after the discovery of gold in California in 1849, used wagon trains across plains populated by warlike Indian tribes. The Army guarded the several transcontinental wagon routes and managed to keep the tribes in check. During the decade of the fifties there were no fewer than twenty-two distinct Indian “wars,” as well as the unusual task of controlling some particularly troublesome settlers.
In 1857 reports filtered back to the east from Utah that the settlement of Mormons there had deliberately massacred a party of Arkansas pioneers at a place called Mountain Meadow. The settlers, having been attacked by a party of Indians, surrendered to a Mormon militia contingent posing as rescuers and allowed themselves to be disarmed. On September 11, 1857, the Mormons summarily executed 120 of the survivors: men, women, and all children over the age of ten. Seventeen children were “adopted” by the Mormons but were later returned east to their relatives. This and other instances of defiance of federal authority prompted the dispatch of two sizable military expeditions from Fort Leavenworth. However, despite some tensions, a full-scale “Mormon War” never became a reality.
Army expeditions such as those from Fort Leavenworth, marching through primitive country where no local procurement was possible, had to carry all requirements, from horseshoe nails to artillery. Supplying the frontier posts, some as far as a thousand miles from inland waterways, entailed great effort. All goods had to be hauled in wagons or carried by pack train. The difficulty of supplying posts in the arid regions of the Southwest led in 1855 to an interesting experiment, strongly backed by Secretary of War Jefferson Davis, in the use of camels as pack animals. Seventy-five were imported from the Middle East and sent to Texas. They showed that they could