Israel claims to be looking for a Palestinian "partner" to reach agreements on many issues, with land distribution of primary importance. If Israel proceeds on its own without Palestinian agreement, I believe there is a concensus in the international community that mideast tensions would lead to increased violence that would threaten Israeli interests. Internal Palestinian disorder will only reduce the prospects of finding a viable partner to negotiate with, and will not lead to increased Israeli security. Now that Israeli elections are over, this should make it easier for Israeli politicians to take actions that support Abbas for a change. Inaction, of course, brought in Hammas.
Police disperse hundreds in brawl in Kafr Manda, northern Israel (Haaretz)
from the article: Gunfight erupts between Hamas and Fatah forces in Gaza