Avi K:1. On the contrary, joining the IDF is avodat Hashem.
2. On the contrary, much has been written. The Tzitz Eliezer wrote a set called “Hilchot Medina”. Rav Herzog wrote several books. There have been many articles in “Techumin” and other Torah journals.
Joining the IDF is most certainly not Avoidas Hashem. Do you think that something can be considered Rotzon Hashem if it involves putting oneself in a situation where adherence to Shulchan Aruch is impossible?