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.
§ 1396. The first part of this clause, respecting laying a duty on tonnage, has been already considered. The remaining clauses have their origin in the same general policy and reasoning, which forbid any state from entering into any treaty, alliance, or confederation; and from granting letters of marque and reprisal. In regard to treaties, alliances, and confederations, they are wholly prohibited. But a state may, with the consent of congress, enter into an agreement, or compact with another state, or with a foreign power. What precise distinction is here intended to be taken between treaties, and agreements, and compacts is nowhere explained; and has never as yet been subjected to any exact judicial, or other examination. A learned commentator, however, supposes, that the former ordinarily relate to subjects of great national magnitude and importance, and are often perpetual, or for a great length of time; but that the latter relate to transitory, or local concerns, or such, as cannot possibly affect any other interests, but those of the parties.[1] But this
