change in the political leadership of the country. Webster, Clay,
Calhoun, John Quincy Adams, not to mention others, all died near
the middle of the century, and their political power passed to
younger men. Adams gave his blessing to a young friend and
co-laborer, William H. Seward of New York, intimating that he
expected him to do much to curb the threatening power of the
slaveholding oligarchy; while Andrew Jackson, who died earlier,
had already conferred a like distinction upon young Stephen A.
Douglas. There was no lack of aspirants for the fallen mantles.

John C. Calhoun continued almost to the day of his death to
modify his interpretation of the Constitution in the interest of
his section. As a young man he avowed protectionist principles.
Becoming convinced that slave labor was not suited to
manufacture, he urged South Carolina to declare the protective
tariff laws null and void within her limits. When his section
seemed endangered by the distribution of anti-slavery literature
through the mail, he extemporized a theory that each State had a
right to pass statutes to protect itself in such an emergency, in
which case it became the duty of the general Government and of
all other States to respect such laws. When it finally appeared
that the territory acquired from Mexico was likely to remain
free, the same statesman made further discoveries. He found that
Congress had no right to exclude slavery from any Territory
belonging to the United States; that the owners of slaves had
equal rights with the owners of other property; that neither
Congress nor a territorial authority had any power to exclude
slaves from a Territory. This doctrine was accepted by extremists
in the South and was finally embodied in the Dred Scott decision
of 1857.