In the long series of acts of indirect aggression, the first was the strenuous agitation by citizens of the Northern States, in Congress and out of it, of the question of Negro emancipation in the Southern States.

The second step in this path of evil consisted of acts of the people of the Northern States, and in several instances of their governments, aimed to facilitate the escape of persons held to service in the Southern States and to prevent their extradition when reclaimed according to law and in virtue of express provisions of the Constitution.  To promote this object, legislative enactments and other means were adopted to take away or defeat rights which the Constitution solemnly guaranteed.  In order to nullify the then existing act of Congress concerning the extradition of fugitives from service, laws were enacted in many States forbidding their officers, under the severest penalties, to participate in the execution of any act of Congress whatever.  In this way that system of harmonious cooperation between the authorities of the United States and of the several States, for the maintenance of their common institutions, which existed in the early years of the Republic was destroyed; conflicts of jurisdiction came to be frequent, and Congress found itself compelled, for the support of the Constitution and the vindication of its power, to authorize the appointment of new officers charged with the execution of its acts, as if they and the officers of the States were the ministers, respectively, of foreign governments in a state of mutual hostility rather than fellow-magistrates of a common country peacefully subsisting under the protection of one well-constituted Union.  Thus here also aggression was followed by reaction, and the attacks upon the Constitution at this point did but serve to raise up new barriers for its defense and security.

The third stage of this unhappy sectional controversy was in connection with the organization of Territorial governments and the admission of new States into the Union.  When it was proposed to admit the State of Maine, by separation of territory from that of Massachusetts, and the State of Missouri, formed of a portion of the territory ceded by France to the United States, representatives in Congress objected to the admission of the latter unless with conditions suited to particular views of public policy.  The imposition of such a condition was successfully resisted; but at the same period the question was presented of imposing restrictions upon the residue of the territory ceded by France.  That question was for the time disposed of by the adoption of a geographical line of limitation.