It is not, because the US Constitution guarantees the right to free speech and free expression, and the US Constitution is the highest law in the land.
It may be ill advised to say the ‘N’ word, but it’s not illegal.
Especially since the majority of blacks (not all, but most), use that same expression with each other. Double standards suck. I'm a white female. I don't use that term, and when I worked in Corrections, and black inmates would call each other that in my presence, I'd tell them not to say it in front of me. I can remember when the standard and accepted term for blacks, was "colored." Then in the late 60's and early 70's, the accepted term was African-American. I said "colored person" one time to a young college student who was interning at the Dept. of Social Services where I was working back then, and she snidely said "Oh, what color were they?" The accepted terms for blacks have changed repeatedly over the years: Colored, African-American, black, person of color, etc. I wish they'd find one, and stick with it.
What’s worse is that he was also THINKING of the N word. (see we can’t even bring ourselves to say it )
Thinking it is a hate crime. Like when you kill someone
(it should be a lesser of a crime if you kill someone while loving them) and there is no constitutional protection for your thoughts. Even now we are being patrolled by the thought police.