The protective system, loudly denounced as unequal and oppressive, as well as unconstitutional, had proved wholly insufficient to arouse rebellion in 1832. It would have proved equally so in 1861: but then the ultra free trade tariff of 1856 was still in existence; and it continued in force, until, to increase dissatisfaction, and invite the very system which they pretended to oppose and deplore, the conspirators in Congress, having power to defeat the 'Morrill Tariff,' deliberately stepped aside, and suffered it to become a law. But this was merely a piece of preliminary strategy intended to give them some advantage in the great battle which was eventually to be fought on other fields. It might throw some additional weight into their scale; it might give them some plausible ground for hypocritical complaint; and might even, to some extent, serve to hide the real ground of their movement; yet, of itself, it could never be decisive of anything. It could neither justify revolution in point of morals, nor could it blind the people of the South to the terrible calamities which the experiment of secession was destined to bring upon them. Slavery alone, with the vast material prosperity apparently created by it, with the debatable and exciting questions, moral, political, and social, which arise out of it, and with the palpable dangers, which, in spite of every effort to deny it, plainly brood over the system--slavery alone had the power to produce the civil war, and to shake the continent to its foundations. In the present crisis of the struggle, it would be a waste of time and of thought to attempt to trace back to its origin the long current of excitement on the slavery question, beginning in 1834, and swelling in magnitude until the present day; or to seek to fix the responsibility for the various events which marked its progress, from the earliest agitation down to the great rebellion, which is evidently the consummation and the end of it all. The only lesson important to be learned, and that which is the sum of all these great events, plainly taught by the history of this generation, and destined to characterize it in all future time, is, that slavery had in itself the germs of this profound agitation, and that, for thirty years, it stirred the moral and political elements of this nation as no other cause had power to do. It is of little consequence, for the purpose in view, to inquire what antagonisms struggled with slavery in this immense contest, covering so great an area in space, and so long a period of time. All ideas and all interests were involved. Moral, social, political, and economical considerations clashed and antagonized in the gigantic conflict.