As Schanzer explains, the violence "was a clear and outward manifestation of a civil war" that began in 1987. As recent events reveal, it isn't over yet. Hamas doubtless understands that Israel's military mission in Gaza could end with the restoration of Fatah's position in Gaza. In fact, it is difficult to imagine how Fatah could do this absent Israeli intervention. Fatah is not strong enough to challenge Hamas through force of arms. Nor can Fatah regain power at the ballot box: Hamas would win or, were that in question, Hamas would not permit a fair vote.
Of course, the outcome of the current battle between Hamas and Israel remains uncertain. Hamas continues to launch missiles at Israeli villages - even as its spokesmen and supporters decry a growing humanitarian crisis in Gaza. In other words, Hamas believes that by simultaneously displaying defiance and exploiting Palestinian suffering it can score a victory in the media and in international forums - which is at least as valuable as winning on the ground.
But should Hamas leaders be wrong, should their best, brightest and most brutal be killed, and should their organization emerge from this conflict crippled, Fatah will be a major beneficiary.
What are the alternatives? Few Israelis have the stomach for a re-occupation of Gaza at this point. The Egyptians, who controlled the territory from 1949 to 1967, have shown no interest in taking responsibility again, not even on an interim basis.
Does this imply that Fatah members are secretly hoping - maybe even helping -- Israel to prevail over Hamas? Possibly, though even if that's true it doesn't mean Fatah will henceforth show good will and a spirit of compromise toward Israel.
In the Middle East, the enemy of my enemy can be useful - but that doesn't make him my friend.