The constitution was swept aside with "charter of negative liberties".
The backup, That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.
Secession is simpler and easier. You have a functioning Govt from the get go.