he subject of slavery,
according to a prescription of Congress. The sentiment is now general,
if not universal, that Congress had no constitutional power to impose
the restriction. This was frankly admitted at the bar, in the course
of this argument. The principles which this court have pronounced
condemn the pretension then made on behalf of the legislative
department. In Groves _v._ Slaughter, (15 Pet.,) the Chief Justice
said: "The power over this subject is exclusively with the several
States, and each of them has a right to decide for itself whether it
will or will not allow persons of this description to be brought
within its limits." Justice McLean said: "The Constitution of the
United States operates alike in all the States, and one State has the
same power over the subject of slavery as every other State." In
Pollard's Lessee _v._ Hagan, (3 How., 212,) the court say: "The United
States have no constitutional capacity to exercise municipal
jurisdiction, sovereignty, or eminent domain, within the limits of a
State or elsewhere, except in cases where it is delegated, and the
court denies the faculty of the Federal Government to add to its
powers by treaty or compact."

This is a necessary consequence, resulting from the nature of the
Federal Constitution, which is a federal compact among the States,
establishing a limited Government, with powers delegated by the people
of distinct and independent communities, who reserved to their State
Governments, and to themselves, the powers they did not grant. This
claim to impose a restriction upon the people of Missouri involved a
denial of the constitutional relations between the people of the
States and Congress, and affirmed a concurrent right for the latter,
with their people, to constitute the social and political system of
the new States. A successful maintenance of this claim would have
altered the basis of the Constitution. The new States would have
become members of a Union defined in part by the Constitution and in
part by Congress. They would not have been admitted to "this Union."
Their sovereignty would have been restricted by Congress as well as
the Constitution. The demand was unconstitutional and subversive, but
was prosecuted with an energy, and aroused such animosities among the
people, that patriots, whose confidence had not failed during the
Revolution, began to despair for the Constitution.[4] Amid the utmost
violence of this extraordinary contest, the