The second session of the 29th Congress was opened in December, 1847. The President’s message was chiefly in relation to the war with Mexico, which had been declared by almost a unanimous vote in Congress. Mr. Calhoun spoke against the declaration in the Senate, but did not vote upon it. He was sincerely opposed to the war, although his conduct had produced it. Had he remained in the cabinet, to do which he had not concealed his wish, he would, no doubt, have labored earnestly to have prevented it. Many members of Congress, of the same party with the administration, were extremely averse to the war, and had interviews with the President, to see if it was inevitable, before it was declared. Members were under the impression that the war could not last above three months. The reason for these impressions was that an intrigue was laid, with the knowledge of the Executive, for a peace, even before the war was declared, and a special agent dispatched to bring about a return to Mexico of its exiled President, General Santa Anna, and conclude a treaty of peace with him, on terms favorable to the United States. And for this purpose Congress granted an appropriation of three millions of dollars to be placed at the disposal of the President, for negotiating for a boundary which should give the United States additional territory. While this matter was pending in Congress, Mr. Wilmot of Pennsylvania introduced and moved a proviso, “_that no part of the territory to be acquired should be open to the introduction of slavery_.” It was a proposition not necessary for the purpose of excluding slavery, as the only territory to be acquired was that of New Mexico and California, where slavery was already prohibited by the Mexican laws and constitution. The proviso was therefore nugatory, and only served to bring on a slavery agitation in the United States. For this purpose it was seized upon by Mr. Calhoun and declared to be an outrage upon and menace to the slaveholding States. It occupied the attention of Congress for two sessions, and became the subject of debate in the State Legislatures, several of which passed disunion resolutions. It became the watchword of party—the synonym of civil war, and the dissolution of the Union. Neither party really had anything to fear or to hope from the adoption of the proviso—the soil was free, and the Democrats were not in a position to make slave territory of it, because it had just enunciated as one of its cardinal principles, that there was “_no power in Congress to legislate upon slavery in Territories_.” Never did two political parties contend more furiously about nothing. Close observers, who had been watching the progress of the slavery agitation since its inauguration in Congress in 1835, knew it to be the means of keeping up an agitation for the benefit of the political parties—the abolitionists on one side and the disunionists or nullifiers on the other—to accomplish their own purposes.