Of the many questions that have been asked about the jaw-dropping success of the New York Knicks' Jeremy Lin, who went from a barely known basketball player to one of the most famous athletes in America in a single game, one that has yet to be posed is: what is the connection between Lin and Mickey Rooney in Breakfast at Tiffany's? While that aesthetically beautiful but morally bankrupt film is primarily remembered for Audrey Hepburn's Givenchy wardrobe, it is Rooney's turn as the speech-impaired upstairs neighbour, Mr Yunioshi, that, for me, really gives the movie its true flavour. It's hard to call a film glamorous when it features a white actor playing an Asian stereotype that would put a Tintin cartoon to shame.

Which brings us back to Lin. Lin is an Asian American NBA basketball player, a first-generation son of Taiwanese immigrants and a Harvard graduate, the American dream given athletic form. Until 4 February, few even knew his name, but after that evening's game against the New Jersey Nets, in which he scored 25 points, and his continuing near-superhuman run of form ever since, the whole of New York and the American press entered into a state of "Linsanity" to the point that Lin is trying to trademark the coinage.

There have been high-profile Asian-American athletes before, Michelle Kwan and Tiger Woods being the most obvious. There have also been Asian players in the NBA before, such as the now-retired 7ft 6in Yao Ming. But Lin is the first American in the league of Chinese or Taiwanese descent and this, it turns out, has been a difficult concept for some to grasp.

One shouldn't expect thoughtful sensitivity from professional athletes or the most hysterical wing of the sports media, but the racist language and even flat-out racism directed at Lin has been quite something to behold.

"Chink in the armor" was ESPN's take not once but twice when the Knicks lost a game last week, both as a headline added by ESPN writer Anthony Federico and then as a phrase used by the anchor Max Bretos (Federico has since been fired and Bretos received a 30-day suspension.) Those two muppets look the height of sophisticated decorum compared with Foxsports.com writer Jason Whitlock, whose response to Lin's triumph over the Lakers on Friday night was to tweet "Some lucky lady in NYC is gonna feel a couple inches of pain tonight", a comment notable for being almost more misogynistic than racist. When the Madison Square Garden Network flashed up a photo of Lin, it superimposed it with a fortune cookie, presumably refraining from adding some chopsticks purely because it didn't have the graphics.

Welterweight Floyd Mayweather has never been a modern-day Emily Post but his tweeted thought on Lin last week – "Jeremy Lin is a good player but all the hype is because he's Asian. Black players do what he does every night and don't get the praise" – was impressive even by his standards. Also, "don't get the praise"? Come on, Floyd, you came ninth in Dancing with the Stars! How much more praise do you want?

Nor does one need to look to the morons for examples. Chinstroking journal the Atlantic put forward the charming theory that Lin's success is due to his "philosophical heritage" – ah, so! And so inscrutable, too!

Racism in sport is nothing new, as anyone familiar with English football could tell you. But Lin's high-profile success has highlighted a different problem, that of racism against Asian Americans in general. While no one would claim that racism against black people is no longer a problem in America, it is unthinkable that any news network or even half-brained TV presenter would use racial slurs against a black player equivalent to the Asian ones that have been used against Lin. This is because racism against Asians is not confronted as much and therefore is somehow seen as more acceptable – not even racist, even.

A survey last year found that Asian American teenagers suffered far more bullying at school than any other demographic: 54% of Asian-American teenagers reported being bullied compared with 31.3% of white teens and 38.4% of black ones. In an extraordinary article in New York magazine last year, Wesley Yang wrote that to be an Asian American means being not just part of a "barely distinguishable" mass of "people who are good at math and play the violin, but a mass of stifled, repressed, abused, conformist quasi-robots who simply do not matter, socially or culturally".

Asian Americans are, without question, barely represented culturally. Black roles in Hollywood are still by and large limited to maids, drug dealers and James Earl Jones, but Asian roles are invariable limited to camp villains, martial arts experts, dippy shop owners and exchange students soundtracked with a gong.

So the answer to what connects Mickey Rooney and Jeremy Lin is that both reveal a side of America that even this most racially aware country tends to ignore. The difference is that Rooney encouraged those stereotypes, Lin overturns them, yet the response remains the same.