I've seen friends of mine have the Circumcision Discussion and the Baby Earrings discussion, and I know it can be done with a lot more tact than by calling someone's culture "backwards" or "savage".

(Also, I have to admit, whenever I hear White people call India "primitive" or "backwards", the part of me that wanted to be an archaeology major thinks, "there were well planned cities in the Subcontinent when Europe was just learning to farm".)