Defining an 'American' Shouldn't be This Hard

"Where are you from?"
It is a question I used to get all the time, no matter where I was in the country, because of my Spanish accent, but I don't hear it as much anymore. Some time ago I decided that I finally lived in a post-accent society.
But I was confronted with reminders of my "otherness" Tuesday when I opened the New York Times and read about the plight of Mebrahtom Keflezighi, the amazing winner of the New York City Marathon. He was the first American to win that race since 1982. Keflezighi, you see, never ran competitively before he immigrated to the United States at the age of 12, the story says. A California resident, he is an American citizen and a product of American distance running programs.
But soon after his victory, the skeptics started raining on his parade. He was born in Eritrea, as foreign a place as they come for the online (and mostly anonymous) critics, so he's not really an American. Worse, one said, he's "just another African marathon winner."
The twist in this story is that East Africans dominate in long-distance running, and some believe this is genetically explained. But scientists looking for proof of such genetic prowess have come back empty-handed.
To me, the story has a familiar ring -- criticism based on the usual intolerance for those who don't look or sound like expected, who don't fit the all-American mold, whatever that may be.
What makes an American American these days? Place of birth? Citizenship? Values? Paying American taxes? Ranting against illegal immigrants on Fox or CNN? Flaunting religion?
After 22 years as an American -- and a running career that includes an Olympic silver medal won for the United States, of course, in the 2004 games in Athens -- Keflezighi can't still bask in national pride.
Isn't it enough he shortened his name to Meb?