Im so torn..

I don't know what to do?? I'm currently 29 weeks with my first baby boy, I'm full white and my fiancé is full Mexican/Hispanic so our baby will obviously be half white and half Mexican. I want the baby to be circumcised, and he doesn't. We had never talked about it until last night when I brought it up. He got mad and said he doesn't want it done cause he wants his son to be like him, and that he will teach him everything. In my family this is something you do, all the white guys I've been with have had it done. I know it's a Mexican cultural thing to not do it, but we can't agree, would I be bad if I just didn't tell him and took our son and got it done later on? I just need advice and input ladies.