In fact this is a great counter example. The two separated in a bloody civil war and since they are both recognized, independent states. It would be the Palestinians' decision whether they want one or two states. Please note that according to the Hamas Charter, Abbas and the rest of the PA are traitors, since they are - God forbid - prepared to negotiate a peaceful solution with Israel that is not based on the destruction of Israel.
Suspect Bangkok bomber arrested, found with possible bomb-making materials (Reuters)
from the article: Disengage from Gaza once and for all