Disclosure: I'm Israeli, I'm anti war and anti occupation. I was drafted more than 20 years ago (it's sort of mandatory here).
I think you paint it in a too much simple colours. In the war between israel and Gaza now, both armies fight for what they believe is the safety of their home, and in both armies there are high numbers if drafted (by force people). Also, in both sides, there is a level of truth that without the auctions of their army their home will be at risk. So you end up in a situation where there is an army that you don't fully agree with and you serve in it since the alternative is even worse.
It boils down to the fact that your political leaders are not having your well-being at the top of their priorities. I believe that your discussion with that someone should be about that. Not about do/don't draft but how to promote a world where there will be no need for drafting.
(I believe that the same goes to Ukrain and Russia war).
Simply reverse the picture of what you said you'll see we are saying the same thing. From Hammas /Palestinians perspective Israel and the settlements are the same and their agenda is to drive away all Palestinians (and to be fair, some of the MKs here say that openly, even before October 7th). From Israel perspective, Hammas's declared agenda is to kill Israel/all the Jews (I mean, it is in their charter). From both perspective, there is a good drive to join the army in order to protect their loved ones.