Is it racist?

A friend of mine recently came under attack on Facebook for a comment she made.

She said  that was was out somewhere and was being gawked at and told the man "What the hell are you looking at? Damn Mexican"

Two people on her friends list went on and on how she was being racist and offensive. One said that she will soon have a Mexican nephew and that my friend needs to watch what she says. Then she went on to post my friend's previous posts about comments her 5 year old son says and using that to make her point on how racist she is.

But the fact was, none of it was racist. Mentioning a person's race to describe them or to ask a question about them doesn't make you racist. And its hardly appropriate to call an innocent 5 year old racist. My son calls our friend from Africa "black guy" cause  he can't pronounce his name, and our friend finds it funny. He doesn't saying it in a mean way, its just what he sees.
I have never been offended by being called white, American, Christian, Southern, or any other true descriptive term. Even plus sized. Guess what, I AM WHITE, AMERICAN, CHRISTIAN, SOUTHERN, and PLUS SIZED!! I'm proud of it. So why should a Mexican be offended by being called a Mexican? Or a black person being referred to as "the black man/woman? Or any other race or religion.
And I don't understand how someone of one race could be offended by hearing another race being called out. That is the most absurd thing I have ever heard. And if you were born here in the States, you ARE NOT considered a Mexican, an African-American or whatever else. You are an AMERICAN. I'm pretty sure blacks in Germany don't refer to themselves as African Germans.
Accept who you really are and stop trying to make yourself seem like something you aren't. And stop trying to be a victim!
I'm not sitting over here bitching and moaning about how the English raped and murdered and tortured and pillaged the Scots for hundreds of years. I'm not claiming they owe my family restitution because we had to flee Scotland and come to America for a better life. So why are whites still being blamed for all the hardships of every other race? If white Europeans could overcome all the hell they had to go through to build this country, and actually win its freedom, and did it by pulling together, don't you think your race should be able to do the same?
Hey blacks, if you're sick of being labeled "thugs", "violent", "niggers", or being classified as people who are lazy, will never do anything but spit out illegitimate kids for more welfare money, or have so many of your men in prisons, THEN WORK ON CHANGING IT! It isn't a stereotype anymore. Its statistics!
If Hispanics are sick of being labeled "illegal immigrants" then get your fucking citizenship! Stop expecting the same freedoms and assistance and healthcare as actual Americans just because you jumped our border. Those that actually worked for their citizenship hate you as much as those born on American soil.
Jews, don't want to be labeld as cheap whiners Then stop being cheap whiners.
The list goes on and on and on. If you don't like the stereotypes, then change them! And stop calling people racist just because you don't like hearing the truth.