One of the biggest drawback of Hinduism is the cast system, these bozo (the learned people who captured Sanskrit and manipulated in their favor) divided people by cast, we already have race ( Mongol and Aryan ). People of Tarai and Himal do not go along; because we never practiced inter cast marriage, which would have brought more positive outcomes.
I do not see any dissimilarity between Nazi and Our Learned People of Sanskrit (whatever written in Sanskrit is taken religiously   who brought the cast system) their object was to purify their race.  
Inter-cast marriage strengthens the race, it brings a new combined gene which is the best proven by science, that is one of the main reason they tried to implement Puste and gotra system. Weren’t the very smart but got all these mess?