It's a reference to Arrested Development. There's also no need to take it personally -- not to mention that both Arizona and California are in the same country (thus making it by definition not nationalistic to say you prefer one to the other).
Preferring a State over another State is exactly the same as nationalism, even if they happened to be united under the same country at a given time (see Calexit).
The Catalonians wanting to separate is also nationalism, despite the proposed country not existing.
