t as to cause them to be
frivolous."[484] In Brolan _v._ United States[485] the Court again
stressed the absolute nature of Congress's power over foreign commerce,
saying: "In the argument reference is made to decisions of this court
dealing with the subject of the power of Congress to regulate interstate
commerce, but the very postulate upon which the authority of Congress to
absolutely prohibit foreign importations as expounded by the decisions
of this court rests is the broad distinction which exists between the
two powers and therefore the cases cited and many more which might be
cited announcing the principles which they uphold have obviously no
relation to the question in hand."[486]

INTERSTATE COMMERCE; CONFLICT OF DOCTRINE AND OPINION

The question whether Congress's power to regulate commerce "among the
several States" embraced the power to prohibit it furnished the topic of
one of the most protracted debates in the entire history of the
Constitution's interpretation, a debate the final resolution of which in
favor of Congressional power is an event of first importance for the
future of American Federalism. The issue was as early as 1841 brought
forward by Henry Clay, in an argument before the Court in which he
raised the specter of an act of Congress forbidding the interstate slave
trade.[487] The debate was concluded ninety-nine years later by the
decision in United States _v._ Darby, in which the Fair Labor Standards
Act was sustained. The resume of it which is given below is based on
judicial opinions, arguments of counsel, and the writings of jurists and
political scientists. Much of this material was evoked by efforts of
Congress, from about 1905 onward, to stop the shipment interstate of the
products of child labor.

ACTS OF CONGRESS PROHIBITIVE OF INTERSTATE COMMERCE

The earliest such acts were in the nature of quarantine regulations and
usually dealt solely with interstate transportation. In 1884 the
exportation or shipment in interstate commerce of livestock having any
infectious disease was forbidden.[488] In 1903 power was conferred upon
the Secretary of Agriculture to establish regulations to prevent the
spread of such diseases through foreign or interstate commerce.[489] In
1905 the same official was authorized to lay an absolute embargo or
quarantine upon all shipments of cattle from one State to another when
the public necessity might demand it.[490] A statute passed in 1905
forbade th