You could just as easily argue that multi-culturalism brought down the Roman empire. Original Rome was based on the values of patrician familien and with Greek philosophy as its base. The Greeks fled to Rome. Then with empire came naturalisation of citizens that were not ethnic Europeans, jews and other semittes.
"During the Byzantine–Sasanian War of 602–628 many Jews sided against the Eastern Roman Empire in the Jewish revolt against Heraclius, which successfully assisted the invading Persian Sassanids in conquering all of Roman Egypt and Syria. In reaction to this further anti-Jewish measures were enacted throughout the Eastern Roman realm and as far away as Merovingian France.[10] Soon thereafter, 634, the Muslim conquests began, during which many Jews initially rose up again against their Eastern Roman rulers.[11]"
They've been at this thing for 2000 years.
"During the Byzantine–Sasanian War of 602–628 many Jews sided against the Eastern Roman Empire in the Jewish revolt against Heraclius, which successfully assisted the invading Persian Sassanids in conquering all of Roman Egypt and Syria. In reaction to this further anti-Jewish measures were enacted throughout the Eastern Roman realm and as far away as Merovingian France.[10] Soon thereafter, 634, the Muslim conquests began, during which many Jews initially rose up again against their Eastern Roman rulers.[11]"
They've been at this thing for 2000 years.