In the defence of Southern interests Mr. Calhoun in the Senate at first appealed to reason and patriotism. It is true that he now became a partisan, but he had been sent to Congress as the champion of the cotton lords. He was no more unpatriotic than Webster, who at first, as the representative of the merchants of Boston, advocated freer trade in the interests of commerce, and afterwards, as the representative of Massachusetts at large, turned round and advocated protective duties for the benefit of the manufacturer. It is a nice question, as to where a Congressman should draw the line of advocacy between local and general interests. What are men sent to Congress for, except to advance the interests intrusted to them by their constituents? When are these to be merged in national considerations? Calhoun's mission was to protect Southern interests, and he defended them with admirable logical power. He was one of three great masters of debate in the Senate. No one could reasonably blame him for the opinions he advanced, for he had a right to them; and if he took sectional ground he did as most party leaders do. It was merely a congressional fight. But when, after the tariff of 1828, it appeared to Calhoun that there was no remedy; that protection had become the avowed and permanent policy of the government; that the tobacco and cotton of the South, being the chief bulk of our exports, were paying tribute to Northern manufactures, which were growing strong under protection of Federal taxes on competing imports; and that the South was menaced with financial ruin,--he took a new departure, the first serious political error of his life, and became disloyal to the Union. In July, 1831, he made an elaborate address to the people of South Carolina, in which, discussing the theoretical relations of the States to the Union, he put forth the doctrine that any State could nullify the laws of Congress when it deemed them unconstitutional, as he regarded the existing tariff to be. He looked upon the State, rather than the Union of States, as supreme, and declared that the State could secede if the Union enforced unconstitutional measures. This, as Von Hoist points out, practically meant that, "whenever different views are entertained about the powers conferred by the Constitution upon the Federal government, those of the _minority_ were to prevail,"--an evident absurdity under a republican government.