Racism is believing that a certain race is inherently inferior, rather it being the fault of cultural influences. Blacks are not inherently inferior to whites, for instance, though a debate could be made that the "black culture" overemphasizes sports and underemphasizes education. In the same way, Americans are not inherently inferior to to Asians (or for that matter, Europeans), but we're perhaps a bit too complacent and lazy. If you want to succeed in a certain area, you have to work hard in it, you can't expect a job to be given to you on a silver platter.

Bottom line, I guess the difference between a racist and a non-racist is that the first will make his decision based on what you look like, and the second based on how well you act. As long as you don't reject all Asians because the ones at work are idiots, you're not racist :)