Earlier quoted context omitted.
You don't think his rhetoric against undocumented immigrants is racist?
Last time I checked "undocumented" immigrants aren't a race, and they also broke the law. It's not racist to attack people breaking the law.
Lynchings were instigated by an accusation of a crime - the perpetrators could claim they weren't racist, they were just keeping their communities safe! [1]
Japanese internment too had a non-racist pretext: people of Japanese descent were claimed to be disloyal citizens with greater allegiance to Japan (even after being born in the USA or becoming naturalized) than the USA. [2]
We know that the debate about undocumented immigrants isn't about to Europeans who overstay their tourist visas or Canadians sneaking across the border: it is about a single ethnic group (hispanic) who have come across the Mexican border. This means that 'undocumented' can easily be a euphemism for 'hispanic', allowing people to shift racist statements into ostensibly non-racist ones. While not all discussions of undocumented immigrants are racist, some certainly are a form of dog whistle [3]
[1] https://en.wikipedia.org/wiki/Lynching_in_the_United_States#...
[2] https://en.wikipedia.org/wiki/Internment_of_Japanese_America...
[3] https://en.wikipedia.org/wiki/Dog-whistle_politics#United_St...