al law of Connecticut, reprisals
authorized by New Jersey against citizens of New York, and when one
could not cross a ferry without transshipment, does any one suppose he
would have admitted all this as compatible with the government which he
was recommending?

This doctrine of a general concurrent power in the States is insidious
and dangerous. If it be admitted, no one can say where it will stop. The
States may legislate, it is said, wherever Congress has not made a
plenary exercise of its power. But who is to judge whether Congress has
made this plenary exercise of power? Congress has acted on this power;
it has done all that it deemed wise; and are the States now to do
whatever Congress has left undone? Congress makes such rules as, in its
judgment, the case requires; and those rules, whatever they are,
constitute the system.

All useful regulation does not consist in restraint; and that which
Congress sees fit to leave free is a part of its regulation, as much as
the rest.

The practice under the Constitution sufficiently evinces, that this
portion of the commercial power is exclusive in Congress. When, before
this instance, have the States granted monopolies? When, until now, have
they interfered with the navigation of the country? The pilot laws, the
health laws, or quarantine laws, and various regulations of that class,
which have been recognized by Congress, are no arguments to prove, even
if they are to be called commercial regulations (which they are not),
that other regulations, more directly and strictly commercial, are not
solely within the power of Congress. There is a singular fallacy, as I
venture to think, in the argument of very learned and most respectable
persons on this subject. That argument alleges, that the States have a
concurrent power with Congress of regulating commerce; and the proof of
this position is, that the States have, without any question of their
right, passed acts respecting turnpike roads, toll-bridges, and ferries.
These are declared to be acts of commercial regulation, affecting not
only the interior commerce of the State itself, but also commerce
between different States. Therefore, as all these are commercial
regulations, and are yet acknowledged to be rightfully established by
the States, it follows, as is supposed, that the States must have a
concurrent power to regulate commerce.

Now, what is the inevitable consequence of this mode of reasoning? Does
it not admit th