ad supplied itself with the means of self-protection by
calling into existence the veto power of the Federal judiciary. This
made the checks upon the authority of the states operative. But how were
those imposed by the Constitution on the general government itself to be
enforced? Not by the Federal government or any of its organs, since
this would allow it to interpret the Constitution to suit itself. If the
general government should have the right to interpret and enforce the
constitutional limitations on the powers of the states, it would for a
like reason follow that the states should interpret and enforce the
constitutional limitations on the authority of the general government
itself. To carry out in good faith what appeared to be the purpose of
the Constitution, _i.e._, to limit the authority of the general
government as well as that of the states, it would seem to be necessary
to make each the judge of the other's powers. It would devolve then on
the state governments to keep the general government within the bounds
which the Constitution set to its authority.

This could be accomplished, however, in no other way than by a veto on
such acts of the general government as, in the opinion of the state,
exceeded its constitutional authority. Those who believed in a federal
as opposed to a national government and who therefore wished to enforce
the constitutional checks on the general government, were irresistibly
impelled toward the doctrine of nullification as the sole means of
protecting the rights of the states.

As Von Holst says, "Calhoun and his disciples were not the authors of
the doctrine of nullification and secession. That question is as old as
the Constitution itself, and has always been a living one, even when it
has not been one of life and death. Its roots lay in the actual
circumstances of the time, and the Constitution was the living
expression of these actual circumstances."[134]

Madison, in _The Federalist_, refers in a vague and indefinite manner to
the power of a state to oppose an unjustifiable act of the Federal
government.

"Should an unwarrantable measure of the Federal government," he says,
"be unpopular in particular states ... the means of opposition to it are
powerful and at hand. The disquietude of the people; their repugnance,
and perhaps refusal, to co-operate with the officers of the union; the
frowns of the executive magistracy of the state; the embarrassments
created by legislat