MARSHALL, C. J. The appellant contends that this decree is erroneous because the laws which purport to give the exclusive privilege it sustains are repugnant to the constitution and laws of the United States. They are said to be repugnant—1st. To that clause in the constitution which authorizes congress to regulate commerce. 2d. To that which authorizes congress to promote the progress of science and useful arts....

As preliminary to the very able discussions of the constitution which we have heard from the bar,. and as having some influence on its construction, reference has been made to the political situation of these states, anterior to its formation. It has been said that they were sovereign, were completely independent, and were connected with each other only by a league. This is true. But, when these allied sovereigns converted their league into a government, when they converted their congress of ambassadors, deputed to deliberate on their common concerns, and to recommend measures of general utility, into a legislature, empowered to enact laws on the most interesting subjects, the whole character in which the states appear underwent a change, the extent of which must be determined by a fair consideration of the instrument by which that change was effected.

This instrument contains an enumeration of powers expressly granted by the people to their government. It has been said that these powers ought to be construed strictly. But why ought they to be so construed? Is there one sentence in the constitution which gives countenance to this rule? In the last of the enumerated powers, that which grants, expressly, the means for carrying all others into execution, congress is authorized "to make all laws which shall be necessary and proper" for the purpose. But this limitation on the means which may be used, is not extended to the powers which are conferred; nor is there one sentence in the constitution, which has been pointed out by the gentlemen of the bar, or which we have been able to discern, that prescribes this rule. We do not, therefore, think ourselves justified in adopting it. I What do gentlemen mean by a construction ?

If they contend only against that enlarged construction which would extend words beyond their natural and obvious import, we might question the application of the term, but should not controvert the principle. If they contend for that narrow construction which, in support of some theory not to be found in the constitution, would deny to the government those powers which the words of the grant, as usually understood, import, and which are consistent with the general views and objects of the instrument, for that narrow construction, which would cripple the government, and render it unequal to the objects for which it is declared to be instituted, and to which the powers given, as fairly understood, render it competent; then we cannot perceive the propriety of this strict construction, nor adopt it as the rule by which the constitution is to be expounded. As men whose intentions require no concealment, generally employ the words which most directly and aptly express the ideas they intend to convey, the enlightened patriots who framed our constitution, and the people who adopted it, must be understood to have employed words in their natural sense, and to have intended what they have said.

The words are: "congress shall have power to regulate commerce with foreign nations, and among the several States, and with the Indian tribes." The subject to be regulated is commerce; and our constitution being, as was aptly said at the bar, one of enumeration, and not of definition, to ascertain the extent of the power, it becomes necessary to settle the meaning of the word. The counsel for the appellee would limit it to traffic, to buying and selling, or the interchange of commodities, and do not admit that it comprehends navigation. This would restrict a general term, applicable to many objects, to one of its significations. Commerce, undoubtedly, Is traffic, but it is something more, it is intercourse. It describes the commercial intercourse between nations, and parts of nations, in all its branches, and is regulated by describing rules for carrying on that intercourse. The mind can scarcely conceive a system for regulating commerce between nations which shall exclude all laws concerning navigation, which shall be silent on the admission of the vessels of the one nation into the ports of the other, and be confined to prescribing rules for the conduct of individuals, in the actual employment of buying and selling, or of barter. If commerce does not include navigation, the government of the Union has no direct power over that subject, and can make no law prescribing what shall constitute American vessels, or requiring that they shall be navigated by American seamen. Yet this power has been exercised from the commencement of the government, has been exercised with the consent of all, and has been understood by all to be a commercial regulation. All America understands, and has uniformly understood, the word "commerce" to comprehend navigation. It was so understood, and must have been so understood, when the constitution was framed. The power over commerce, including navigation, was one of the primary objects for which the people of America adopted their government, and must have been contemplated in forming it. The convention must have used the word in that sense, because all have understood it in that sense; and the attempt to restrict it comes too late.

If the opinion that "commerce," as the word is used in the constitution, comprehends navigation also, requires any additional confirmation, that additional confirmation is we think, furnished by the words of the instrument itself....

The word used in the constitution, then, comprehends, and has been always understood to comprehend, navigation within its meaning; and a power to regulate navigation is as expressly granted as if that term had been added to the word "commerce." To what commerce does this power extend? The constitution informs us, to commerce "with foreign nations, and among the several states, and with the Indian tribes." It has, we believe, been universally admitted that those words comprehend every species of commercial intercourse between the United States and foreign nations. No sort of trade can be carried on between this country and any other to which this power does not extend. It has been truly said that commerce, as the word is used in the constitution, is a unit, every part of which is indicated by the term.

If this be the admitted meaning of the words in its application to foreign nations, it must carry the same meaning throughout the sentence, and remain a unit, unless there be some plain intelligible cause which alters it. The subject to which the power is next applied is to commerce "among the several states." The word "among" means intermingled with. A thing which is among others is intermingled with them. Commerce among the states cannot stop at the external boundary line of each state, but may be introduced into the interior. It is not intended to say that these words comprehend that commerce, which is completely internal, which is carried on between man and man in a state, or between different parts of the same state, and which does not extend to or affect other States. Such a power would be inconvenient and is certainly unnecessary. Comprehensive as the word "among" is, it may very properly be restricted to that commerce which concerns more States than one. The phrase is not one which would probably have been selected to indicate the completely interior traffic of a state, because it is not an apt phrase for that purpose; and the enumeration of the particular classes of commerce to which the power was to be extended would not have been made had the intention been to extend the power to every description. The enumeration presupposes something not enumerated; and that something, if we regard the language or the subject of the sentence must be the exclusively internal commerce of a state. The genius and character of the whole government seem to be, that its action is to be applied to all the external concerns of the nation, and to those internal concerns which affect the states generally; but not to those which are completely within a particular state, which do not affect other states, and with which it is not necessary to interfere for the purpose of executing some of the general powers of the government. The completely internal commerce of a state then, may be considered as reserved for the state itself.

But, in regulating commerce with foreign nations, the power of congress does not stop at the jurisdictional lines of the several states. It would be a very useless power if it could not pass those lines. The commerce of the United States with foreign nations is that of the whole United States. Every district has a right to participate in it. The deep streams which penetrate our country in every direction pass through the interior of almost every state in the Union, and furnish the means of exercising this right. If congress has the power to regulate it, that power must be exercised whenever the subject exists. If it exists within the states, if a foreign voyage may commence or terminate at a port within a state, then the power of congress may be exercised within a state....

The power of congress, then, whatever it may be, must be exercised within the territorial jurisdiction of the several States. The sense of the nation on this subject is unequivocally manifested by the provisions made in the laws for transporting goods by land between Baltimore and Providence, between New York and Philadelphia, and between Philadelphia and Baltimore.

We are now arrived at the inquiry, What is this power? It is the power to regulate; that is, to prescribe the rule by which commerce is to be governed. This power, like all others vested in congress, is complete in itself, may be exercised to its utmost extent and acknowledges no limitations other than are prescribed in the constitution. These are expressed in plain terms, and do not affect the questions which arise in this case, or which have been discussed at the bar. If, as has always been understood, the sovereignty of congress, though limited to specified objects, is plenary as to those objects, the power over commerce with foreign nations, and among the several states, is vested in congress as absolutely as it would be in a single government, having in its constitution the same restrictions on the exercise of the power as are found in the constitution of the United States.... The power of congress, then, comprehends navigation within the limits of every state in the Union, so far as that navigation may be, in any manner, connected with "commerce with foreign nations, or among the several States, or with the Indian tribes." It may, of consequence, pass the jurisdiction line of New York, and act upon the very waters to which the prohibition now under consideration applies.

But it has been urged with great earnestness that, although the power of congress to regulate commerce with foreign nations, and among the several states, be coextensive with the subject itself, and have no other limits than are prescribed in the constitution, yet

The states may severally exercise the same power within their respective jurisdictions. In support of this argument, it is said that they possessed it as an inseparable attribute of sovereignty before the formation of the constitution, and still retain it, except so far as they have surrendered it by that instrument; that this principle results from the nature of the government, and is secured by the tenth amendment; that an affirmative grant of power is not exclusive, unless in its own nature it be such that the continued exercise of it by the former possessor is inconsistent with the grant, and that this is not of that description. . . .

In discussing the question, whether this power is still in the states, in the case under consideration, we may dismiss from it the inquiry, whether it is surrendered by the mere grant to congress, or is retained until congress shall exercise the power. We may dismiss that inquiry, because it has been exercised, and the regulations which congress deemed it proper to make, are now in full operation. The sole question is, Can a State regulate commerce with foreign nations and among the States while Congress is regulating it? Â Â . . .

[Here the Chief Justice examined the acts of Congress of 1796 and 1799 directing federal officers to assist in the execution of the quarantine and health laws of a State, the act of 1803 prohibiting the importation of slaves into any State which shall itself prohibit their importation, and the act of 1789 acknowledging a concurrent power in the States to regulate the conduct of pilots. ]

These acts were cited at the bar for the purpose of showing an opinion in congress, that the states possess, concurrently with the legislature of the Union, the power to regulate commerce with foreign nations and among the states. Upon reviewing them, we think, they do not establish the proposition they were intended to prove. They show the opinion that the states retain powers enabling them to pass the laws to which allusion has been made, not that those laws proceed from the particular power which has been delegated to congress.

It has been contended by the counsel for he appellant that, as the word "to regulate’ implies in its nature full power over the

thing to be regulated, it excludes, necessarily the action of all the others that would perform the same operation on the same thin. That regulations is designed for the entire result, applying to those parts, which remain as they were, as to those which remain as they were, as well as to those which are altered. It produces a uniform whole, which is as much disturbed and deranged by changing what the regulating power designs to leave untouched as that on which it is as much disturbed and degraded by changing what the regulating power designs to leave untouched as that on which it has operated. There is great force in this argument, and the court is not satisfied that it has been refuted. Since, however, in exercising the power of regulating their own purely internal affairs, whether of trading or police, the states may sometimes enact laws the validity of which depends on their interfering with, and being contrary to, an act of congress passed in pursuance of the constitution, the court will enter upon the inquiry, whether the laws of New York, as expounded by the highest tribunal of that state, have, in their application to this case, come into collision with an act of congress, and deprived a citizen of a right to which that act entitles him. Should this collision exist, it will be immaterial whether those laws were passed in virtue of a concurrent power "to regulate commerce with foreign nations and among the several states," or in virtue of a power to regulate their domestic trade and police. In one case and the other the acts of New York must yield to the law of congress; and the decision sustaining the privilege they confer against a right given by a law of the Union, must be erroneous. This opinion has been frequently expressed in this court, and is founded as well on the nature of the government as on the words of the constitution. In argument, however, it has been contended that, if a law passed by a state in the exercise of its acknowledged sovereignty, comes into conflict with a law passed by congress in pursuance of the constitution, they affect the subject, and each other, like equal opposing powers. But the framers of the constitution foresaw this state of things, and provided for it by declaring the supremacy not only of it but also of the laws made in pursuance of it. The nullity of any act inconsistent with the constitution is produced by the declaration that the constitution is supreme law.... In every such case the act of congress, or treaty, is supreme; and the law of the state, though enacted in the exercise of powers not controverter, must yield to it....

The court is aware that in stating the train of reasoning by which we have been conducted to this result, much time has been consumed in the attempt to demonstrate propositions, which may have been thought axioms.... But it was unavoidable....

Powerful and ingenious minds, taking as postulates that the powers expressly granted to the government of the Union are to be contracted, by construction, into the narrowest possible compass, and that the original powers of the states are to be retained, if any possible construction will retain them, may, by a course of well-digested, but refined and metaphysical reasoning, founded on these premises, explain away the constitution of our country and leave it a magnificent structure indeed, to look at, but totally unfit for use. They may so entangle and perplex the understanding as to obscure principles, which were before thought quite plain, and induce doubts where, if the mind were to pursue its own course none would be perceived. In such a case, it is peculiarly necessary to recur to safe and fundamental principles, to sustain those principles, and, when sustained, to make them the tests of the arguments to be examined.

Decree of Court of New York reversed and annulled and bill of Aaron Ogden dismissed.