by the annexation of her territory to the United States,[62] with the proviso that from her great area might in the future be cut off still four other States. Slavery had been abolished in all Mexican territory, and Texas had been properly a "free" country; but in becoming a part of the United States she became also a slave State. Mexico had declared that annexation of Texas would constitute a _casus belli_, yet she was wisely laggard in beginning vindictive hostilities against a power which could so easily whip her, and she probably never would have done so had the United States rested content with an honest boundary line. But this President Polk would not do, and by theft and falsehood he at last fairly drove the Mexicans into a war, in which they were so excessively beaten that the administration found itself able to gather more plunder than it had expected. By the treaty of peace the United States not only extended unjustly the southwestern boundary of Texas, but also got New Mexico and California. To forward this result, Polk had asked the House to place $2,000,000 at his disposal. Thereupon, as an amendment to the bill granting this sum, Wilmot introduced his famous proviso, prohibiting slavery in any part of the territory to be acquired. Repeatedly and in various shapes was the substance of this proviso voted upon, but always it was voted down. Though New Mexico had come out from under the rule of despised Mexico as "free" country, a contrary destiny was marked out for it in its American character. A plausible suggestion was made to extend the sacred line of the Missouri Compromise westward to the Pacific Ocean; and very little of the new country lay north of that line. By all these transactions the South seemed to be scoring many telling points in its game. They were definite points, which all could see and estimate; yet a price, which was considerable, though less definite, less easy to see and to estimate, had in fact been paid for them; for the antagonism of the rich and teeming North to the Southern institution and to the Southern policy for protecting it had been spread and intensified to a degree which involved a menace fully offsetting the Southern territorial gain. One of the indications of this state of feeling was the organization of the "Free Soil" party.