Resolved , That negro slavery, as it exists in fifteen states of this Union, composes an important portion of their domestic institutions, inherited from their ancestors, and existing at the adoption of the Constitution, by which it is recognized as constituting an important element in the apportionment of power among the states, and that no change of opinion or feeling on the part of the non_slaveholding states of the Union, in relation to this institution, can justify them, or their citizens, in open or covert attacks thereon, with a view to its overthrow; and that all such attacks are in manifest violation of the mutual and solemn pledge to protect and defend each other given by the states respectively on entering into the constitutional compact which formed the Union, and are a manifest breach of faith, and a violation of the most solemn obligations.