Don't beat yourself up. You've not studied theology and doctrine as intensely as your priest. There's no such thing as a stupid question and you should from time to time take the initiative to write him your thoughts in seeking spiritual guidance. From a casual glance at history, it's pretty clear that Christianity isn't particularly tolerant of the ideas present in the ideology of multiculturalism, but sadly, many of the clergy who endorse it are men of no faith. History has shown that Christianity can co-exist among honorable heathens, it cannot thrive when it's adherents are unaware that evil cannot be outrun. That it must be both understood and confronted as it will always adapt and pursue. That said, while Christianity does allow for a variance of cultures, as you can see in Polish, Irish, Italian, German, Spanish, American, and so on reverence for the faith. This is only possible because the populace strives to maintain a common standard in alignment with Christian doctrine. That standard being a belief that Jesus Christ is our only lord and savior, and that the way we understand as Christianity is core to instructing and informing the moral and ethical framework of our people and society. Variant cultures do not equal multiple cultures. Another lie Multiculturalism spreads is that Jesus was a refugee, when in fact his parents and he were full citizens of Rome. You cannot be a refugee in your own country.