in 1810.
Thus thirty years saw an increase of nearly seven-fold in the population of this region.[28]
Meanwhile, slavery had become the issue of the day. The slave power was in control of the Federal Government, and in order to maintain its authority, it needed new slave states to offset the free states that were being carved out of the Northwest.
Here were three forces—first the desire of the frontiersmen for "elbow room"; second the demand of King Cotton for unused land from which the extravagant plantation system might draw virgin fertility and third, the necessity that was pressing the South to add territory in order to hold its power. All three forces impelled towards the Southwest, and it was thither that population pressed in the years following 1820.
3. Texas
Mexico lay to the Southwest, and therefore Mexico became the object of American territorial ambitions. The district now known as Texas had constituted a part of the Louisiana Purchase (1803); had been ceded to Spain (1819); had been made the object of negotiations looking towards its purchase in 1826; had revolted against Mexico and been recognized as an independent state in 1835.
Texas had been settled by Americans who had secured the permission of the Mexican Government to colonize. These settlers made no effort to conceal their opposition to the Mexican Government, with which they were entirely out of sympathy. Many of them were seeking territory in which slavery might be perpetuated, and they introduced slaves into Texas in direct violation of the Mexican Constitution. The Americans did not go to Texas with any idea of becoming Mexican subjects; on the contrary, as soon as they felt themselves strong enough, they declared their independence of Mexico, and began negotiations for the annexation of Texas to the United States.
The Texan struggle for independence from Mexico was cordially welcomed in all parts of the United States, but particularly in the South. Despite the protests of Mexico, public meetings were held; funds were raised; volunteers were enlisted and equipped, and supplies and munitions were sent for the assistance of the Texans in ships openly fitted out in New Orleans.
No sooner had the Texans established a government than the campaign for annexation was begun. The advocates of annexation—principally Southerners—argued in favor of adding so rich and so logical a prize to the territory of the United States, citing the purchase of Louisiana and of Florida as precedents. Their opponents, first on constitutional grounds and then on grounds of public policy, argued against annexation.
Opinion in the South was greatly aroused. Despite the fact that many of her foremost statesmen were against annexation, some of the Southern newspapers even went so far as to threaten the dissolution of the Union if the treaty of ratification failed to pass the Senate.
The campaign of 1844 was fought on the issue of annexation and the election of James K. Polk was a pledge that Texas should be annexed to the United States. During the campaign, the line of division on annexation had been a party line—Democrats favoring; Whigs opposing. Between the election and the passage of the joint resolution by which annexation was consummated, it became a sectional issue—Southern Whigs favoring annexation and Northern Democrats opposing it.
So strong was the protest against annexation, that the treaty could not command the necessary two-thirds vote in the Senate. The matter was disposed of by the passage of a joint resolution (March 1, 1845) which required only a majority vote in both houses of Congress. President Polk therefore took office with the mandate of the country and the decision of both houses of the retiring Congress, in favor of annexation.
Mexico, in the meantime, had offered to recognize the independence of Texas and to make peace with her if the Texas Congress would reject the joint resolution, and refuse the proffered annexation. This the Texas Congress refused, and with the passage, by that body, of an act providing for annexation, the Mexican minister was withdrawn from Washington, and Mexico began her preparations for war.
President Polk had taken office with the avowed intention of buying California from Mexico. The rupture threatened to prevent him from carrying this plan into effect. He therefore sent an unofficial representative to Mexico in an effort to restore friendly relations. Failing in that, he and his advisers determined upon war as the only feasible method of obtaining California and of settling the diplomatic tangle involved in the annexation of Texas.
4. The Conquest of Mexico
The Polk Administration made the Mexican War as a part of its expansionist policy.
"Although that unfortunate country (Mexico) had officially notified the United States that the annexation of Texas would be treated as a cause of war, so constant were the internal quarrels in Mexico that open hostilities would have been avoided had the conduct of the Administration been more honorable. That was the opinion of Webster, Clay, Calhoun, Benton, and Tyler. … Mexico was actually goaded on to war. The principle of the manifest destiny of this country was invoked as a reason for the attempt to add to our territory at the expense of Mexico."[29]
After the annexation of Texas it became the duty of the United States to defend that state against the threatened Mexican invasion.
Mexican troops had occupied the southern bank of the Rio Grande. General Zachary Taylor with a small force, moved to a position on the Nueces River. Between the two rivers lay a strip of territory the possession of which was one of the sources of dispute between Mexico and Texas. What followed may be stated in the words of one of the officers who participated in the expedition: "The presence of the United States troops on the edge of the territory farthest from the Mexican settlements was not sufficient to provoke hostilities. We were sent to provoke a fight, but it was essential that Mexico begin it" (p. 41). "Mexico showing no willingness to come to the Nueces to drive the invaders from her soil, it became necessary for the 'invaders' to approach to within a convenient distance to be struck. Accordingly, preparations were begun for moving the army to the Rio Grande, to a point near Matamoras. It was desirable to occupy a position near the largest center of population possible to reach without actually invading territory to which we set up no claim whatever" (p. 45).[30]
The occupation, by the United States troops, of the disputed territory soon led to a clash in which several United States soldiers were killed. The incident was taken by the President as a sufficient cause for the declaration of a state of war. The House complied readily with his wishes, passing the necessary resolution. Several members of the Senate begged for a delay during which the actual state of affairs might be ascertained. The President insisted, however, and the war was declared (May 13, 1846).
The declaration of war was welcomed with wild enthusiasm in the South. Meetings were called; funds were raised; volunteers were enlisted, equipped and despatched in all haste to the scene of the conflict.
The North was less eager. There were protests, petitions, demonstrations. Many of the leaders of northern opinion took a public stand against the war.
