The Federalist Papers by Alexander Hamilton, John Jay, and James Madison

2. "No State shall, without the consent of the Congress, lay any imposts

or duties on imports or exports, except what may be absolutely necessary for executing its inspection laws, and the net produce of all duties and imposts laid by any State on imports or exports, shall be for the use of the treasury of the United States; and all such laws shall be subject to the revision and control of the Congress. No State shall, without the consent of Congress, lay any duty on tonnage, keep troops or ships of war in time of peace, enter into any agreement or compact with another State, or with a foreign power, or engage in war unless actually invaded, or in such imminent danger as will not admit of delay." The restraint on the power of the States over imports and exports is enforced by all the arguments which prove the necessity of submitting the regulation of trade to the federal councils. It is needless, therefore, to remark further on this head, than that the manner in which the restraint is qualified seems well calculated at once to secure to the States a reasonable discretion in providing for the conveniency of their imports and exports, and to the United States a reasonable check against the abuse of this discretion. The remaining particulars of this clause fall within reasonings which are either so obvious, or have been so fully developed, that they may be passed over without remark. The SIXTH and last class consists of the several powers and provisions by which efficacy is given to all the rest.