When South Carolina began her resistance to the tariff in 1830, times had changed, and with them the popular conception of the government established by the Constitution. It was now a much more serious thing to threaten the existence of the Federal government than it had been in 1799, or even in 1814. The great fabric which had been gradually built up made an overthrow of the government look very terrible; it made peaceable secession a mockery, and a withdrawal from the Union equivalent to civil war. The boldest hesitated to espouse any principle which was avowedly revolutionary, and on both sides men wished to have a constitutional defence for every doctrine which they promulgated. This was the feeling which led Mr. Calhoun to elaborate and perfect with all the ingenuity of his acute and logical mind the arguments in favor of nullification as a constitutional principle. At the same time the theory of nullification, however much elaborated, had not altered in its essence from the bald and brief statement of the Kentucky resolutions. The vast change had come on the other side of the question, in the popular idea of the Constitution. It was no longer regarded as an experiment from which the contracting parties had a right to withdraw, but as the charter of a national government. "It is a critical moment," said Mr. Bell of New Hampshire to Mr. Webster, on the morning of January 26, "and it is time, it is high time that the people of this country should know what this Constitution _is_." "Then," answered Mr. Webster, "by the blessing of heaven they shall learn, this day, before the sun goes down, what I understand it to be." With these words on his lips he entered the senate chamber, and when he replied to Hayne he stated what the Union and the government had come to be at that moment. He defined the character of the Union as it existed in 1830, and that definition so magnificently stated, and with such grand eloquence, went home to the hearts of the people, and put into noble words the sentiment which they felt but had not expressed. This was the significance of the reply to Hayne. It mattered not what men thought of the Constitution in 1789. The government which was then established might have degenerated into a confederation little stronger than its predecessor. But the Constitution did its work better, and converted a confederacy into a nation. Mr. Webster set forth the national conception of the Union. He expressed what many men were vaguely thinking and believing, and the principles which he made clear and definite went on broadening and deepening until, thirty years afterwards, they had a force sufficient to sustain the North and enable her to triumph in the terrible struggle which resulted in the preservation of national life. When Mr. Webster showed that practical nullification was revolution, he had answered completely the South Carolinian doctrine, for revolution is not susceptible of constitutional argument.