The topic of discussion for this Constitution Monday comes from Article I, Section 10, Clause 3: "No State shall, without the Consent of Congress, … enter into any Agreement or Compact with another State, or with a foreign Power…." This clause simply declares that no State has the right to make any agreements that would impact other states or involve the entire nation.
"The constitutional logic of the provisions reflects a profound insight. Fearing that `factions,' or interest groups, operating at the state level would endanger the Union and the legitimate interests of sister-states, Madison urged the Convention to include a congressional `negative' of `state laws in all cases whatsoever.' … The Convention instead subjected state laws to the operation of the Supremacy Clause: state laws become and remain in effect unless they are inconsistent with federal law or the Constitution" (Michael S. Greve in The Heritage Guide to the Constitution, p. 178).
"In a very real sense this provision anticipated and tried to prevent the tragic circumstances which led to the American Civil War. A combination of `secession' and `confederation' in violation of this provision cost the American people nearly a million lives. It is important to point out, however, that there were violations of the Constitution on both sides before the contending forces finally erupted in civil war. It is also interesting that the threat of secession and a separate confederation was a haunting spectre which had hung over the United States almost from its inception. New England … was talking of secession and a separate confederation clear up until the end of the War of 1812."