Rambam, Hilchot Melachim 3,2
?????????? ?????? ??????? ?????????? ????????? ??? ????? ????????????? ?????????? ????? ????????? ????? ????? ??????????????? ????????????? ?????????? ????? ????????? ????????. ?????????? ????? ????????? ?????? ????????. ??????????? (????? ? ? ??) “?????? ??? ???????????????? ??????????? ??????? ??????? ????????????”?. ????????? ??? ????????? ????????? ???????? ??????????? ??????????? ???????? ??????????? (????? ? ? ??) “????? ???????????? ??????????” (????? ? ? ??) “?????? ???????? ?????????????”:
Ibid 6,1
????? ??? ???? ????????? ??????? ??? ????????? ???????? ????????. ??????????? ???????. ????????? ?????????? ?????? ??? ??????? ????????.
Ibid 7,4
??????? ????????? ????????? ??????????????? ????????? ?????? ?????????? ???????????? ???????????? ?????????. ????? ???????????? ??????? ????? ????????? ?????????? ????? ????????? ???????? ???????????:
The Netziv (Heemek Devar Devarim 17,15) and Rav Kook (Miushpat Cohen 144) say that any leader chosen by the public has the status of a king for these matters. Rav Schachter quoted Rav Yaakov Kaminetzky as telling his grandson that if lived in Israel, he would be obligated to serve. He hs a shiur on e subject which can be heard online. Rav Zevin also condemned draft dodgers. You can read it (�R. Shelomo Yosef Zevin on the Drafting of Yeshiva Students� (TRADITION, Fall 1985)) online.
The fact is that nobody goes OTD because of the IDF. They would have gone OTD anyway,as anyone who lives in a Chareidi area knows.