ncreasing numbers, how
was it possible to regard the States as watertight compartments? At
least, then, when local legislative programs break down on account of
the division of the country into States, it becomes the clear duty of
Congress to adopt supplementary legislation to remedy the situation. In
doing so, it is not undermining the Federal System; it is supporting it,
by making it viable in modern conditions. The assemblage of the States
in one Union was never intended to put one State at the mercy of
another. If, however, well considered programs of legislation are
rendered abortive in a State in consequence of the flow of commerce into
it from other States, then it becomes the duty--certainly it is within
the discretion of Congress--which alone can govern commerce among the
States, to supply the required relief. _See_ especially Assistant
Attorney General Maury's argument. In re Rapier, 143 U.S. 110, 127-129
(1892).

In this connection the advocates of this view cited discussion
contemporaneous with Jefferson's Embargo, and under the embargo itself,
as supporting their position. In the case of the Brigantine William the
validity of the embargo was challenged before the United States District
Court of Massachusetts on the ground that the power to regulate commerce
did not embrace the power to prohibit it. Judge Davis answered: "It will
be admitted that partial prohibitions are authorized by this expression;
and how shall the degree, or extent, of the prohibition be adjusted, but
by the discretion of the National Government, to whom the subject
appears to have been committed? * * * The power to regulate commerce is
not to be confined to the adoption of measures, exclusively beneficial
to commerce itself, or tending to its advancement; but, in our national
system, as in all modern sovereignties, it is also to be considered as
an instrument for other purposes of general policy and interest. * * *
the national right, or power, under the Constitution, to adapt
regulations of commerce to other purposes, than the mere advancement of
commerce, appears to be unquestionable. * * * The situation of the
United States, in ordinary times, might render legislative
interferences, relative to commerce, less necessary; but the capacity
and power of managing and directing it, for the advancement of great
national purposes, seems an important ingredient of sovereignty." And in
confirmation of this argument Judge Davis cited the claus