National Secession convention, isn't that self-contradictory?

There has been a lot of reporting on a "national secession convention." Isn't that self-contradictory? By making it a "national" activity, aren't they admitting that they are just playing games within the "national" context. A North American secession convention might make sense, or an anti-national convention might make sense. However, secession is about leaving a nation and not being national at all.

What I see is some "Ruritanian" fantasy playing. "What if we had our own toy Republic," is the fantasy without considering that when the day is over, you are on your own.