Finishing out the tenth section of Article One.
No State shall, without the Consent of Congress, lay any Duty of 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.
States cannot charge a tax on the freight of ships in their ports unless they had Congressional Consent. States also can’t have standing armies and battleships in peacetime. They could have a State Militia, which is every able-bodied man. States also need Congressional approval for any deal or contract with another state or foreign country. And finally, States cannot declare war on another state or country unless they were invaded or about to be where there’s no time.
This actually completes Article One of the Constitution. Next week we see how much power the President and the Executive Branch really have.