It is amazing to me that President Trump has not, on a rare day when he's in New York, exited Trump Tower, made a sharp left, and limoed down to Stuyvesant High School. It is New York City's crown jewel, where − like in the fictional Lake Wobegon − all the students really are "above average." And just to make matters more intriguing and complicated, Stuyvesant's student body is majority Asian. The mayor thinks this is a "monumental injustice" and that more of them should be Hispanic and black. For that, he recently asked a black church for an "amen."

Instead, from certain critics, he got a groan of opposition and disbelief. In the name of racial equity, fairness and that most deceptive of all words, diversity, he would demolish a system that at Stuyvesant and seven other elite city high schools has, without a doubt, propelled countless poor kids right into the middle class − and beyond.

The reason I mentioned Trump in the first paragraph − besides enticing you to read what I've written − is that his base consists, in no small part, of white males who think the deck is stacked against them; that the liberal policies of the Obama years, personified by Hillary Clinton, unfairly favored other groups or, when it came to trade, other nations. You and I may quibble with this view, but then along comes Bill de Blasio to demand an "amen" to his efforts to tilt a color-blind admissions system to get a different blend.

Blacks and Hispanics comprise 67 percent of New York's public school students. Yet Stuyvesant's incoming freshman class contains only 10 blacks, 27 Hispanics, 151 whites − and 613 Asians. A similar imbalance applies to the city's seven other elite schools, including Brooklyn Tech, where the mayor's son just graduated. Clearly, something is off. In the best of all possible worlds, these schools should have student bodies that reflect the city's demographics. This, though, is not the best of all worlds. It's the one we have.

And in this world, the children of Asian immigrants walk away with the lion's share of admissions. Why? Simple. They study. They study hard. Admissions to New York's academically elite schools is based solely on an entrance exam. That's it. No alumni recommendations. No offer of a contribution. No athletic ability or anything of the sort. Take the test. Score high. Get in. That's it. Nothing could be fairer. Yet, de Blasio wants to do away with the exam all together.

In an exhaustive piece for the City Journal about Brooklyn's Chinese-American community − one of New York's several "Chinatowns" − Kay S. Hymowitz writes that "If, as sometimes appears the case, 'Harvard' is the first English word that immigrant Chinese mothers learn, the second is probably 'Stuyvesant.'" Just reading Hymowitz's description of how these parents work around the clock for their children − rising before dawn to ensure that the homework is done − is exhausting in itself. Often, they put aside money to have their kids prepped for the Stuyvesant admissions test. This is not a perk of the rich. This is yet another sacrifice these parents make for their children.

My limited tolerance for affirmative action − possibly permissible when the poor are advantaged at the expense of the rich − hits a wall in this case. By and large, the Asian-Americans of Stuyvesant are not rich. Many of them are poor, so-called Title I kids, entitled to all sorts of aid. They and their parents played by the rules and studied hard. Why should they be deprived of what they earned on the basis of race or ethnicity? That's what the mayor wants to happen. Asian kids have to make way for black or Hispanic ones.

The figures are both stark and tragic. But they prove, to the obstinate blindness of the doctrinaire, that poverty is not always the determinant. You can hardly get poorer than many of the Asian immigrants. They come to America with little. They often can't even speak the language. In her article, Hymowitz says that Chinese families often "maintain that they have been discriminated against, and they tell their children to expect discrimination as well." It's a hard, hard life.

Already, the mayor has reserved some slots for students who almost pass the exam so that more black and Hispanic kids will be admitted to the special schools. For him, it is only a beginning. In the name of diversity, he wants to scrap the test and, thereby, destroy a system that epitomized the American dream and − as Trump might say − made America great.

Richard Cohen's column is distributed by the Washington Post News Service.