The part of this debate which excited no attention at the time, but has since acquired a momentous importance, is that part in which Mr. Calhoun declared his favorable disposition to the Missouri compromise, and his condemnation of Mr. Randolph (its chief opponent), for opposing it; and his change of opinion since, not for unconstitutionality, but because he believed it to have become dangerous in encouraging the spirit of abolitionism. This compromise was the highest, the most solemn, the most momentous, the most emphatic assertion of Congressional power over slavery in a territory which had ever been made, or could be conceived. It not only abolished slavery where it legally existed; but for ever prohibited it where it had long existed, and that over an extent of territory larger than the area of all the Atlantic slave States put together: and thus yielding to the free States the absolute predominance in the Union. Mr. Calhoun was for that resolution in 1820,--blamed those who opposed it; and could see no objection to it in 1838 but the encouragement it gave to the spirit of abolitionism. Nine years afterwards (session of 1846-'47) he submitted other resolutions (five in number) on the same power of Congress over slavery legislation in the territories; in which he denied the power, and asserted that any such legislation to the prejudice of the slaveholding emigrants from the States, in preventing them from removing, with their slave property, to such territory, "would be a violation of the constitution and the rights of the States from which such citizens emigrated, and a derogation of that perfect equality which belongs to them as members of this Union; _and would tend directly to subvert the Union itself_." These resolutions, so new and startling in their doctrines--so contrary to their antecessors, and to the whole course of the government--were denounced by the writer of this View the instant they were read in the Senate, and, being much discountenanced by other senators, they were never pressed to a vote in that body; but were afterwards adopted by some of the slave State legislatures. One year afterwards, in a debate on the Oregon territorial bill, and on the section which proposed to declare the anti-slavery clause of the ordinance of 1787 to be in force in that territory, Mr. Calhoun denied the power of Congress to make any such declaration, or in any way to legislate upon slavery in a territory. He delivered a most elaborate and thoroughly considered speech on the subject, in the course of which he laid down three propositions: