a change by that method
except under stress of war or great popular excitement. That idea is now
exploded. We of to-day know better, having seen the Income Tax Amendment
(No. XVI), the Election of Senators by Popular Vote Amendment (No.
XVII), the Prohibition Amendment (No. XVIII), and the Woman Suffrage
Amendment (No. XIX) go through within a period of seven years. For
generations, however, the tradition of constitutional immobility held
sway and the forces of change worked through channels that seemed easier
and less obstructed.

[Footnote 1: No. XVI, the Income Tax Amendment, ratified in 1913.]

The principal channel has been congressional legislation. Congress has
found ways of reaching by indirection objects which could not be
approached directly. Under the express grants of power contained in the
Constitution statutes have been enacted which were really designed to
accomplish some ulterior object. A striking example is found in the
child labor laws, discussed more at length in a subsequent chapter.
Congress at first sought to regulate child labor by a statute enacted
ostensibly as a regulation of commerce under the Commerce Clause of the
Constitution. The Supreme Court held the Act unconstitutional as
exceeding the commerce power of Congress and invading the powers
reserved to the states.[1] Thereupon Congress practically reenacted it,
coupled with a provision for a prohibitive tax on the profits of
concerns employing child labor, as part of a revenue act enacted under
the constitutional grant of power to lay taxes.[2]

[Footnote 1: _Hammer v. Dagenhart_, 247 U.S., 251.]

[Footnote 2: Revenue Act of 1918, Title XII.]

The assumption by the National Government of jurisdiction over the
manufacture and sale of intoxicating liquors is no more of an
encroachment on the prerogatives of the states than is its assumption of
jurisdiction over child labor and the use of narcotic drugs. We come
back, therefore, to the proposition that the Prohibition Amendment is to
be regarded less as a departure in American fundamental law than as a
spectacular manifestation of a change already well under way.

The change, however much students of our institutions may deplore it, is
not difficult to explain. The earlier solicitude for state rights was in
a sense accidental. It was based on sentiment and mutual jealousies
among the colonies rather than on any fundamental differences in race,
beliefs, or material interests. The tradit