An Open Letter to the Moetzet Gedolei HaTorah of Agudath Yisroel of America
I have seen the unofficial response of the Moeztet Gedolei HaTorah and remain very perplexed. Were it not for the importance and urgency of the matter - the honor of God's Name, and life and death for the nation of Israel - I would have remained silent.
One of the greatest issues facing the Jewish nation today is if we have the right to hold on to certain parts of Eretz Israel, even if it will cost Jewish lives. Before we can start tackling this issue, we must first understand that 
Who ever said that we were fighting an obligatory war?
pikuach nefesh and mesirut nefesh is part of war; there is no war in which life is not endangered. With every other mitzvah for which the Torah commands, "Allow yourself to be killed rather than transgress", there is no justification to put yourself in a situation that would warrant this self-sacrifice. Only a Milchemet Mitzvah, a war commanded by the Torah, is a mitzvah for which you must endanger your life from the outset. But who ever said that we were fighting an obligatory war, and what does it have to do with the communities of Judea and Samaria?
The Torah commands us that Eretz Yisrael be under Jewish control, as the Ramban writes, "Behold we were commanded with conquest in every generation." (Supplement to the Rambam, Sefer HaMitzvot, positive commandment #4).
Assuming that the Ramban is not correct, and there is no mitzvah to conquer the Land, is there a justification to continue living and fighting in Judea and Samaria? Can Jews continue to live in Hevron and other dangerous places?
If one looks at the definitions that the Rambam gives for a Milchemet Mitzvah, one of his definitions is, "To save Israel from the hand of the enemy."(Rambam, Mishneh Torah, Hilchot Milachim, 5:1) Due to the fact that today our main enemy sits in Judea and Samaria, there is a need to control that area. But what does that have to do with Jews living in those areas? To fulfill the Rambam's definition of Milchemet Mitzvah, it should be enough just having army bases in those areas.
Speaking as a former soldier, it is much easier to control an area, when there is a friendly population living there. Second, we all know that the best defense is a good offense, and the Halacha clearly understands this: "When it is a city close to the border, then, even if they want to come only for the purpose of (stealing) straw and stubble, we desecrate the Shabbos because of them; for they may conquer the city and from there, the rest of the land will be easy for them to conquer." (Shulchan Aruch, Orach Chaim 329:6) Even the smallest threat against the country must be taken seriously; you do not allow your enemy to even to move a piece of straw from Eretz Yisrael. Because the communities of Judea and Samaria are border communities of the State of Israel, there is even a higher obligation to guard them. If the Jews living in these communities would all leave, it would bring the enemies of Israel even closer to the major population centers, thus endangering the entire Jewish nation.
What specific dangers will an expulsion pose?
1. The expulsion of nearly 300,000 Jews. The lives of 300,000 Jews will be ruined, as will yeshivot, shuls 
What specific dangers will an expulsion pose?
and kollelim, and the beautiful communities will be handed over to the enemy.
2. Surrendering the entire Samarian and Judean mountain range to the enemy (Hamas, Fatah, Islamic Jihad, etc.). Rockets from Hebron will hit Beersheba and Kiryat Gat; Bethlehem will hit Jerusalem; Bodrus will hit Ben-Gurion Airport; Rantis will hit Tel Aviv; Kalkilya will hit Kfar Saba and Raanana; Tulkarem will hit Netanya; Jenin will hit Afula and Nazareth.
3. The surrender of eastern Jerusalem and the Temple Mount. No more visits to the Kotel. Even with Israeli control over eastern Jerusalem and the Temple Mount, the army has shut down the Kotel for hours at a time due to security concerns. In addition, the Jews in western Jerusalem will have to deal with constant rocket and mortar attacks, as did their parents and grandparent up till 1967.
4. The surrender of over 1/3 of Israel's water supply. Israel already faces a severe water crisis. The aquifers of Judea and Samaria are of the highest quality and supply the domestic needs of Jerusalem, Tel Aviv, Beersheba and most of the cities in the center of the country; they are also used for irrigation of large agricultural areas along the coastal plain, the piedmont, the Beersheba valley and the Jezreel Valley.
5. The release of thousands (perhaps tens of thousands) of Arab murderers. This will strengthen the armies of Hamas and Fatah, and destroy the morale of the Israeli army as it watches years of work unravel. Jewish soldiers will understand that they endanger their lives for nothing and draft dodging will increase. In addition, the release will cause grave mental stress to all victims of terror and put the rest the population in harm's way.
There is also another issue involved in the mitzvah to conquer the Land. We learn from Sanhedrin 74a-b, "Rabbi 
Communities of the Galut must do everything in their power to aid and strengthen the border communities.
Yochanan said... in public, even for a minor commandment one should be killed rather than transgress. What is a minor commandment? Rava bar Rabbi Yitzhak said in the name of Rav: even to change the lace of one's shoe." When non-Jews decree that the Jews transgress a mitzvah for the sake of humiliating the Jewish people and the Torah, then there is in fact a mitzvah to give up your life and not transgress. The Gemara even applies this rule to a minhag as insignificant as changing shoelaces.
Today, because the nations have made numerous decrees and resolutions (at the UN, through the EU, etc.) that prohibit the Jewish people from conquering and settling Eretz Yisrael, we have even another reason for self-sacrifice. Even if one could argue that the mitzvah of yishuv-kibush Eretz Yisrael does not apply in our time, I would certainly hope that Eretz Yisrael would rank higher than a shoelace.
To sum up, we are fighting at least one and even possibly two simultaneous Milchemot Mitzva. The first being the Rambam, "To save Israel from the hand of the enemy" and the second by the Ramban, "Behold we were commanded with conquest in ever generation." Either way, the communities of the Judea and Samaria play a vital role in the fulfillment of these two mitzvot.
The Jews living in the communities of the Judea and Samaria, the Jews who are sacrificing themselves for the security of the nation, should be aided and applauded. The communities of the Galut must do everything in their power to aid and strengthen the border communities of Eretz Yisrael.