Well first of all we have to distinguish between the various Asian-American groups. As we do have disadvantaged, underrepresented groups in there as well (specfically some of the SE Asian nationalities, as many are refugees). Fortunately some institutions are realizing that there are different needs that need to be addressed from these communities.
The groups that have done particularly well are South Asians (I just stand in awe of South Asians and their accomplishments in this country), Chinese, Japanese, Korean and now Vietnamese Americans.
Starting in the 1960's, Asians were beneficiaries of the Civil Rights movement as the country quota system for immigration into America was removed. At that time due to various instabilities in Asia (India v Pakistan, China and the Great Leap Forward, the Korean War), the well-educated of those countries left en masse, a brain drain in effect, and the US benefitted. They carried with them from their home countries a high esteem for education. (e.g., in India they created an Indian Institute of Technology in the 1950's modelled exactly after MIT, and IIT actually has the 2nd highest number of graduate students at MIT today. The Confucian countries have always had a tradition of national exams.)
Hence Asians and Asian-Americans will spend a disproportianate share of their family income on educating their kids. And Asian-American kids oftentimes benefit from having two educated adults which provide a good environment, and who knows, possibly good genes too.
Asian-American parents overly encourage their kids to mainly stick with the technology, science and medical sectors as their is more of a merit based measurement there. If you're better, and work harder, you'll most likely be rewarded. That isn't always the case in other fields. Dentistry is one of those fields where what you put into will determine what you get out of it, great no?
I qualify my quick explanation, realizing I probably glossed over large amounts of history. One more thing I'd like to add is that while certain Asians are indeed 3rd, 4th or even 5th generation in this country, the vast majority are still 1st and 2nd generation, in other words recent immigrants. I feel confident that a lot of the tensions and misunderstandings between Asian-Americans and other minority groups was a result of just being too new and not understanding enough. We are just another chapter in America's immigrant story, and we're hopefully becoming well integrated with the whole. While you will see some insular Asian communities, you are also increasingly seeing Asian-Americans become part of mainstream America
