because of historical factors such as colonialism, socioeconomic factors, oppression. etc. otherwise, there is absolutely nothing intrinsic about other races which makes them less capable or less intelligent than other races.  "race realism", apart from being a myth, is also rooted in nazism, genocide, eugenics, fascism, and pseudoscience. we are all one race, the human race. virtually all economic experts agree by this point that immigrants boost the economy by creating jobs and raising the gdp. and not to mention, they make some damn good food. america has always been a nation of immigrants, and if you don't like it, you can just move to another country where immigration isn't allowed.
United States