There is a very simple test to use.
Look and listen to what trump and his cronies are saying, when he/they are telling four Congresswomen to "go back" to whatever country trump/GOP think they're from (even when they were BORN here), when he/they are basically telling them to "LEAVE." Look at the ethnicity - Latino, Black - being attacked by Republicans right now.
Republicans believe Non-Whites are Non-Americans. It's THAT simple.
Every Birther attack (which is coming back to the fore against Kamala Harris), every voter suppression move, every time a prominent Republican accuses an ethnic minority of "hating" the United States... it all ties into that one simple basic fact.
Republicans believe Non-White are Non-Americans. They believe Blacks and Latinos and Chinese and Japanese and Arabs - many of whom can trace their ancestry in the United States back farther than half the GOP - don't count.
THAT makes it racist.
And THAT makes the entire Republican Party a bunch of assholes.