Whether Congress’s power to regulate commerce includes the power to regulate navigation.
Holding
Yes. Commerce includes commercial intercourse in all its branches, including navigation.
Reasoning
The Court rejected the argument that “commerce” means only buying, selling, or exchanging commodities. In constitutional usage, commerce is broader: it is commercial intercourse among nations and states, and navigation is an indispensable means of carrying on that intercourse.
Longstanding national practice confirmed this reading. From the beginning, Congress had regulated vessels, seamen, and navigation as commercial matters, and the Constitution itself refers to vessels, ports, entry, clearance, and duties in provisions governing commercial regulation.
The Court also reasoned that a power to regulate commerce that excluded navigation would be practically hollow. A national commercial system necessarily includes rules governing the vessels that enter ports and move goods and persons between jurisdictions.