This “proviso” was obviously unnecessary to the exclusion of slavery from any “part of the territory to be acquired,” for negro slavery had been long before abolished in New Mexico and in California under Mexican law; and the Democratic party of the United States had laid it down as a cardinal principle of Democratic policy, involved indeed, as many Democrats thought, in the principle of Home Rule, that there was “no power in Congress to legislate upon slavery in the Territories.” The introduction of the “proviso” therefore led, and could lead, solely to an immediately sterile, but eventually most dangerous, inflammation of the public mind on the question of the relations of slavery, as an institution already existing within the Union, to the politics of the country. The “proviso” was defeated in Congress; but the discussion had aroused the abolitionists of the North on the one hand, and the extreme pro-slavery men at the South on the other side, into loud and angry debate; and the opportunity of “forcing an issue” was seized by Mr. Calhoun of South Carolina, a man of the highest character and of keen intellect, who honestly believed that the South must be sooner or later driven in self-defence to withdraw from the Union, and who had brought his State and himself in 1832, on the question of the right of a State to “nullify” a Federal law, within striking distance of the executive authority wielded by the iron hand of President Jackson. Mr. Calhoun introduced into the Senate, on the 19th of February, 1847, a series of resolutions denying the right of Congress to pass any law which would have the effect of preventing any citizen of a slave State from carrying slaves as his property into any territory. No vote was taken on these resolutions, but they served Mr. Calhoun’s purpose of awakening public sentiment at the South to the threatening attitude of the anti-slavery sentiment at the North.