Huh? It has everything to do with closing the boarders to immigration.
Just because they come across the border from Mexico or Canada, doesn’t mean that they are Hispanic, or American-Indian, or White, or whatever. It means that the borders are too porous, and we need to make sure that the enemies of the Nation do not come across those borders.
Oh.... and don't ever think that we are nation building in Afgahnistan. We aren't. We are re-arranging the landscape and letting someone else rebuild. It's harsh; but how much nation building have we done? None. That has been the UN. But then that's another thread and a whole other topic.