When the whackjobs in the palestinian authority speak about the occupation or the occupied territory, they're not talking about the West Bank, rather Israel, the West Bank, and Gaza. Retreat to the 1967/1949 line, that doesn't end the occupation. That's just a wacky as Aztlan claiming the southwest as occupied territory. The difference is that the palestinians have developed a critical mass of supporters who nominally support their agenda, including our Secretary of State.
BTW La Raza has been promoting the concept of a defacto reconquista by establishing themselves and their supporters as a voting majority, not through violence. That's not a far fetched idea at all.
They can certainly attempt to mobilize a voting majority in their fantasy new country, but we've already had a pretty good precedent set on what happens when there's a declaration of secession.
There will never be an Aztlan.