The vast majority of the population is not tribal or xenophobic, and the people who are attacked for being xenophobic are probably just regular Americans who are concerned for America more than immigrants and other countries, and that's not xenophobic.
'concerned for america' is a poor excuse to be tribal or xenophobic. i think there's a clear line between 'undocumented immigrants are a problem' and 'mexicans should leave our country.' the former is an obvious fact and the latter is an insulting and tribal generalization
concern for your country is a legitimate concern, but if that overwhelms the need to think rationally ie. witch hunt then its less of a concern and more of an attack. thats all racism is- feeling threatened unnecessarily and taking out your fear on people who don't deserve it
I think you're vastly overestimating the severity of "racism" and "xenophobia" in America.
There are more racially-motivated attacks in this country every year than there are religiously motivated terrorist attacks. With that in mind i'm sure the severity of "racism" and "xenophobia" can be considered somewhat high