It was, after all, the first attempt which had been made to legislate in relation to slavery on the basis of a principle, and the application of any honest idea to the subject-matter of the controversy served to clear an atmosphere which for thirty years had been clouded by unprincipled compromises.

The methods and the objects of the several different parties were made suddenly definite and unmistakable; and their representatives found it necessary for the first time to stand firmly upon their convictions instead of sacrificing them in order to maintain an appearance of peace.

It soon became apparent that not even this erection of national irresponsibility into a principle would be sufficient to satisfy the South, because the interests of the South had come to demand the propagation of slavery as a Constitutional right, and if necessary in defiance of local public opinion.

Unionists were consequently given to understand that the South was offering them a choice between a divided Union and the nationalization of slavery; and they naturally drew the conclusion that they must de-nationalize slavery in order to perpetuate the Union.

The repeal, consequently, hastened the formation of the Republican party, whose object it was to prevent the expansion of slavery and to preserve the Union, without violating the Constitutional rights of the South.