Question: Is it permissible for combat soldiers fighting in Gaza to eat meat during the Nine Days?
Answer: In general, it is forbidden for Ashkenazim to eat meat from 1 Av (Mishnah Berurah 551:58) and for Sefardim from 2 Av (Kaf Ha-Chaim ibid. #125). A soldier in Tzahal, however, is not defined as Ashkenazi or Sefardi but as a soldier, and it is permissible for a combat soldier to eat meat if it is needed to give him strength. And this is also the ruling of Colonel Ha-Rav Eyal Krim, head of the Halachah Department of Tzahal (Kishrei Milchama 3:56). And the Military Rabbinate also ruled this way.
Question: Can non-combat soldiesr eat meat?
Answer: There is a Chiddush of Maran Ha-Rav. It once happened that there were two restaurants for workers, one Kosher and one not Kosher, and many of the non-religious Jewish workers ate in the Kosher restaurant. During the Nine Days, however, meat was not served in the Kosher restaurant, and the workers who wanted to eat meat would eat in the non-kosher restaurant. The Rabbi, who was responsible from the Poalei Mizrachi, asked Maran Ha-Rav Kook: Is it permissible to serve meat in the Kosher restaurant so that the non-religious Jews would not eat the Treif meat? Rav Kook said that it is permissible since it is a Mitzvah to save Jews from eating Treif. Any such meal is therefore considered a Seudat Mitzvah at which one may eat meat during the Nine Days, and even you - the Rabbi - would be allowed to eat meat there (Moadei Ha-Re'eiyah pp. 539-542)! One could say, based on this, that a meal during which a combat soldier eats meat in order to give him strength to wage war is considered a Seudat Mitzvah, and at a Seudat Mitzvah even a non-combat soldier would be permitted to eat meat. If Rav Kook had given such a ruling, we would certainly accept it, but he did not. So the non-combat soldiers must still refrain from eating meat.