A population of this class, held in subjection, existed in nearly all the States, but was more numerous and of more serious concernment in the South than in the North on account of natural differences of climate and production; and it was foreseen that, for the same reasons, while this population would diminish and sooner or later cease to exist in some States, it might increase in others. The peculiar character and magnitude of this question of local rights, not in material relations only, but still more in social ones, caused it to enter into the special stipulations of the Constitution. Hence, while the General Government, as well by the enumerated powers granted to it as by those not enumerated, and therefore refused to it, was forbidden to touch this matter in the sense of attack or offense, it was placed under the general safeguard of the Union in the sense of defense against either invasion or domestic violence, like all other local interests of the several States. Each State expressly stipulated, as well for itself as for each and all of its citizens, and every citizen of each State became solemnly bound by his allegiance to the Constitution that any person held to service or labor in one State, escaping into another, should not, in consequence of any law or regulation thereof, be discharged from such service or labor, but should be delivered up on claim of the party to whom such service or labor might be due by the laws of his State. Thus and thus only, by the reciprocal guaranty of all the rights of every State against interference on the part of another, was the present form of government established by our fathers and transmitted to us, and by no other means is it possible for it to exist. If one State ceases to respect the rights of another and obtrusively intermeddles with its local interests; if a portion of the States assume to impose their institutions on the others or refuse to fulfill their obligations to them, we are no longer united, friendly States, but distracted, hostile ones, with little capacity left of common advantage, but abundant means of reciprocal injury and mischief. Practically it is immaterial whether aggressive interference between the States or deliberate refusal on the part of any one of them to comply with constitutional obligations arise from erroneous conviction or blind prejudice, whether it be perpetrated by direction or indirection. In either case it is full of threat and of danger to the durability of the Union. Placed in the office of Chief Magistrate as the executive agent of the whole country, bound to take care that the laws be faithfully executed, and specially enjoined by the Constitution to give information to Congress on the state of the Union, it would be palpable neglect of duty on my part to pass over a subject like this, which beyond all things at the present time vitally concerns individual and public security.