Dershowitz can be very exasperating, but I once watched him discuss constitutional issues with a group of other “authorities,” and realized that in his circles, he is, relatively speaking, the most sensible of the lot.
In this case, he is exactly right. This is not to avoid the obvious, which is that there is almost no way for Israel to win, except to depopulate Gaza. Merely winning militarily does not change anything. They must crush the very society which breeds terrorism. I would leave very little there, and deport the survivors to the antipodes.
At the very least, Israel should demand surrender from Hamas. Hamas must crawl to the table. No more of Hamas’s defiant “We will fight to the last drop of blood” unless they really intend to die, in which case they should be helped.
No conflict of this nature ends until one side breaks the will of the other to fight. That’s what the surge did in Iraq, and that’s what haapened to the US in Vietnam despite overwhelmingly winning the military side.
Now, the will to fight can be broken through various means. In WWII, we did it through taking Berlin and uncorking nukes. In Vietnam, they (and their leftist allies here) did it through propaganda and subversion. In Iraq, we did it through the surge and convincing most of the population that we were the good guys.
I don’t know how Israel can do this. I really don’t think the islamiacs can do this to Israel. So this is going to drag on and on and on until Israel figures it out.