Only because it contradicts your favorite historical fantasies.
In fact, both "necessity" and "destructive" conditions are clearly spelled out by our Founders in their 1776 Declaration of Independence.
Founders never intended to imply that any small group could declare itself "independent" for any reason whatever, or indeed, for no reason -- in other words, at pleasure.
DiogenesLamp: "I’ve already shown you that New York clearly regarded the choice to leave as up to the people, and so did Virginia."
But again, only under conditions they listed, including: "necessary", or "perverted to their injury or oppression".
These words are not meaningless, they specifically negate "at pleasure" secession (unless by mutual consent) and refer back to conditions listed in their own 1776 Declaration of Independence.
Again, all of which DiogenesLamp knows but refuses to acknowledge because it contradicts your favorite historical fantasies.
Skip.