The movement of our Army to the Rio Grande was made by the commanding general under positive orders to abstain from all aggressive acts toward Mexico or Mexican citizens, and to regard the relations between the two countries as peaceful unless Mexico should declare war or commit acts of hostility indicative of a state of war, and these orders he faithfully executed.  Whilst occupying his position on the east bank of the Rio Grande, within the limits of Texas, then recently admitted as one of the States of our Union, the commanding general of the Mexican forces, who, in pursuance of the orders of his Government, had collected a large army on the opposite shore of the Rio Grande, crossed the river, invaded our territory, and commenced hostilities by attacking our forces.  Thus, after all the injuries which we had received and borne from Mexico, and after she had insultingly rejected a minister sent to her on a mission of peace, and whom she had solemnly agreed to receive, she consummated her long course of outrage against our country by commencing an offensive war and shedding the blood of our citizens on our own soil.

The United States never attempted to acquire Texas by conquest.  On the contrary, at an early period after the people of Texas had achieved their independence they sought to be annexed to the United States.  At a general election in September, 1836, they decided with great unanimity in favor of “annexation,” and in November following the Congress of the Republic authorized the appointment of a minister to bear their request to this Government.  This Government, however, having remained neutral between Texas and Mexico during the war between them, and considering it due to the honor of our country and our fair fame among the nations of the earth that we should not at this early period consent to annexation, nor until it should be manifest to the whole world that the reconquest of Texas by Mexico was impossible, refused to accede to the overtures made by Texas.  On the 12th of April, 1844, after more than seven years had elapsed since Texas had established her independence, a treaty was concluded for the annexation of that Republic to the United States, which was rejected by the Senate.  Finally, on the 1st of March, 1845, Congress passed a joint resolution for annexing her to the United States upon certain preliminary conditions to which her assent was required.  The solemnities which characterized the deliberations and conduct of the Government and people of Texas on the deeply interesting questions presented by these resolutions are known to the world.  The Congress, the Executive, and the people of Texas, in a convention elected for that purpose, accepted with great unanimity the proposed terms of annexation, and thus consummated on her part the great act of restoring to our Federal Union a vast territory which had been ceded to Spain by the Florida treaty more than a quarter of a century before.