Even if Trump said "I think white people are superior to black people" ... Maybe he doesn't actually believe that white are superior to blacks - but his words would be racist. Because they match up to the dictionary definition.
I disagree. Those words do not fit the OED definition. The OED definition isn't about words. The definition requires knowing another's beliefs.
1 Prejudice, discrimination, or antagonism directed against someone of a different race based on the belief that one's own race is superior.
1.1 The belief that all members of each race possess characteristics, abilities, or qualities specific to that race, especially so as to distinguish it as inferior or superior to another race or races.