Then what was the debate over the Articles of Confederation about? What were the endless debates occurring throughout the nation from 1787-1789 meant to be; merely a pointless debating exercise? Huh, got you there, didn't I?
"The secession of a state from the Union depends on the will of the people of such state....To deny this right would be inconsistent with the principle on which all our political systems are founded, which is, that the people have in all cases, a right to determine how they will be governed."--A View Of The Constitution Of The United States Of America, William Rawle, 1826
The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.--Tenth Amendment
Why, if your premise holds, would the state of Massachusetts, and on a greater scale the New England states during the War of 1812, entertain secession as an option if they knew such an act was illegal?