If Israel falls so will the Ultra Orthodox. Do you want to live in a Jewish state or go back to the pogroms, the ghettos, the Inquisitions of Europe and the religious taxes & restrictions of the Islamic Caliphate in the Middle East (this is assuming you'll be allowed to exist at all in a Palestine state ruled by Hamas). I also find that those of us who are NOT in Israel, those of us who tirelessly defend Israel to our Non-Jewish friends, who defend Israel against a tide of Jew hate from both Islamists and the trendy left, are left increasingly distraught about the logic if you are not prepared to defend your country, how or why are we going to obtain allies to help Israel and the Jewish nation (for allies is exactly what we need to survive).
I would also add, on a personal note, that I KNOW what it is like to have to served in armed forces. I may not have served with the IDF-although their prestige is known worldwide- but with an army of a gentile nation, called Great Britain, in which I was never forbidden to study or read Torah, or told to not be a Jew, but did my part for Queen and Country; I saw comrades, I saw death, I saw duty to defend a country.