It is certainly true that all cultures are not equal. They differ according to their values; which is superior depends on the eye of the beholder, but certainly they are not all equal. Do you think the cultures that worshipped the sun as a god and drank human blood to celebrate it are equal to your own culture?
The Republican brand may be as injured as the Democratic brand was in 1860 and 1896 and 1980, but as you see, the pendulum swings both ways.