>>19508
Technically yes and no.
People of different races come from different regions with different cultures and social norms. When you force them to integrate together in a society, they don't like to do so and will usually polarize. If you look at fights in the Middle East, they're almost exclusively along ethnic lines.
You could potentially force two different races to eventually get along, but at that point you've formed a new ethnicity usually. In America, this is most accurately displayed in folks of Irish-German and Irish-Nordic mixed blood. The English were outbred from 95% of the country, and the Italians lost influence everywhere except the east coast. Virtually all that's left in America are people of German ancestry, Irish ancestry, or some mix of the two. You can actually see this divide as the folks in predominantly German areas tend to be more socialist/lean more to the democratic party (the great plains being the exception), while those of Irish, Nordic, and Scottish ancestry tend to lean more towards the republican party.