So what about that withdrawal business? The first thing we need to do is remove some of the ideological clutter that has sabotaged any hope of reasonable discussion of this topic.

There are those who argue that any withdrawal is immoral, anti-Zionist, anti-Jewish, etc. This rests on one of two claims:
1. In the battle against evil, maximal borders are optimal borders and retrenchment is defeat.
2. The redemption locomotive has left the station, it travels in one direction and you're either on the train or a dog barking at it.

The first claim is simply wrong; it appeals mainly to those who lack the patience or the wit for subtlety.
The second claim is coherent only to those who simultaneously a) subscribe to hyper-Zionist ideology and b) are frum enough to actually take it seriously. In short, kooks.

Conversely, there are those who argue that not withdrawing is immoral, anti-Zionist, anti-Jewish, etc. This also rests on one of two claims:
1. If the above-mentioned ideological arguments against withdrawal are fallacious, then their polar opposite must be true.
2. We have a moral debt to the Arabs.

The first is simply bad reasoning. Nevertheless, it's useful for moral grandstanding (an egregious example of which is Leon Wieseltier's (characteristically) well-written but (characteristically) self-righteous and pompous recent screed).
As for the second: kiss my ass.

So now that that muck is out of the way, what are the real arguments? Serious proponents of the withdrawal make the following arguments:
1. By shortening defense lines and reducing interaction with local Arabs, the defense burden on Israel's security forces is substantially diminished.
2. By disengaging from a large and growing hostile Arab population, we delay the demographic threat to Israel's Jewish character.
3. By making essentially minor concessions, we derail international pressure for far greater concessions.
4. By adopting a centrist position, we reduce internal political tensions which threaten to undermine Israel's social cohesiveness.

Quite an imposing list! Unfortunately, these arguments are mostly specious.

1. Despite what the Israeli Left would have you believe, Gush Katif is geographically disjoint from the major Arab population centers in Azza. (This is not true of Netzarim, Kfar Darom and Morag.) Thus, the major defense burden in Azza is not the defense of the Jewish civilian population there but rather preventive action against terror originating in Azza and directed at Jews both in and out of Azza. In particular, the IDF is engaged in the prevention of smuggling of weapons via Egypt and via the Mediterranean, gathering of intelligence on terrorist operations and destruction of explosives factories. Withdrawal will not diminish the need to carry out these missions. It will, however, make them almost impossible to achieve.

2. To the extent that Arabs in Azza constitute a demographic threat to Israel, that threat will remain after a withdrawal of Jews from Azza. The Arabs aren't going anywhere. Israel is not currently responsible for Arab civilian matters in Azza and Arabs in Azza are not enfranchised in Israel. The demographic threat lies , then, simply in the proximity to Israel of a large hostile population. If we close our eyes, will they disappear?

3. Throwing the EU a bone will not keep them busy for long. It will only whet their appetite for more. As for the U.S., let us not delude ourselves that they are on board with settlement blocs, if they go ballistic at the mention of a few new apartments in Maaleh Adumim. All the concessions made at Oslo and all the terror it engendered have bought us no long-lasting goodwill; they have only invited greater pressure for more far-reaching concessions.

4. There was no consensus for withdrawal from Azza before Sharon set out to create one. (I'm not convinced that there is any such consensus even today.) In fact, Labor was trounced in the last election in no small part because unilateral withdrawal from Azza was a centerpiece of its platform. Creating an artificial consensus for withdrawal and then arguing for withdrawal on grounds of consensus is more than a little disingenuous. And if Sharon's intention is to split the difference between his own former self and the Beilins of the world, he can give up now. There is no red line they won't cross to stay far to his left. Finally, if Sharon thinks that it is only the Left's loyalty to the State that need concern us because the Right is incorruptibly patriotic, he may be underestimating the trauma that this withdrawal will cause. Remember that many children have lived their whole lives in Azza -- and then been buried in its soil.

So what argument do withdrawal supporters have left? Somehow it always comes down to what is essentially an act of intellectual desperation that goes roughly like this: Israel has strategic interests which far outweigh that of remaining in Azza and what must have happened is that the United States promised/threatened to do so-and-so if Israel does/does not carry out the withdrawal. It's all very hush hush, so just take Sharon's word for it and hop aboard.

I personally am not about to abandon reason in order to place my faith in a man whose only two confidantes are Dov Weissglas and Omri Sharon.