San Francisco is a classic example of a city unexcelled in its liberalism. But the black population of San Francisco today is less than half of what it was back in 1970, even though the city's total population has grown.

Severe restrictions on building housing in San Francisco have driven rents and home prices so high that blacks and other people with low or moderate incomes have been driven out of the city. The same thing has happened in a number of other California communities dominated by liberals.

Liberals try to show their concern for the poor by raising the level of minimum wage laws. Yet they show no interest in hard evidence that minimum wage laws create disastrous levels of unemployment among young blacks in this country, as such laws created high unemployment rates among young people in general in European countries.

The black family survived centuries of slavery and generations of Jim Crow, but it has disintegrated in the wake of the liberals' expansion of the welfare state. Most black children grew up in homes with two parents during all that time but most grow up with only one parent today.

Liberals have pushed affirmative action, supposedly for the benefit of blacks and other minorities. But two recent factual studies show that affirmative action in college admissions has led to black students with every qualification for success being artificially turned into failures by being mismatched with colleges for the sake of racial body count.

The two most recent books that show this with hard facts are "Mismatch" by Richard Sander and Stuart Taylor, Jr., and "Wounds That Will Not Heal" by Russell K. Nieli. My own book "Affirmative Action Around the World" shows the same thing with different evidence.

In all these cases, and many others, liberals take positions that make them look good and feel good -- and show very little interest in the actual consequences for others, even when liberal policies are leaving havoc in their wake.

The current liberal crusade for more so-called "gun control" laws is more of the same. Factual studies over the years, both in the United States and in other countries, repeatedly show that "gun control" laws do not in fact reduce crimes committed with guns.

Cities with some of the tightest gun control laws in the nation have murder rates far above the national average. In the middle of the 20th century, New York had far more restrictive gun control laws than London, but London had far less gun crime. Yet gun crimes in London skyrocketed after severe gun control laws were imposed over the next several decades.

Although gun control is not usually considered a racial issue, a wholly disproportionate number of Americans killed by guns are black. But here, as elsewhere, liberals' devotion to their ideology greatly exceeds their concern about what actually happens to flesh and blood human beings as a result of their ideology.

One of the most polarizing and counterproductive liberal crusades of the 20th century has been the decades-long busing crusade to send black children to predominantly white schools. The idea behind this goes back to the pronouncement by Chief Justice Earl Warren that "separate educational facilities are inherently unequal."

Yet within walking distance of the Supreme Court where this pronouncement was made was an all-black high school that had scored higher than two-thirds of the city's white high schools taking the same test -- way back in 1899! But who cares about facts, when you are on a liberal crusade that makes you feel morally superior?

To challenge government-imposed racial segregation and discrimination is one thing. But to claim that blacks get a better education if they sit next to whites in school is something very different. And it is something that goes counter to the facts.

Many liberal ideas about race sound plausible, and it is understandable that these ideas might have been attractive 50 years ago. What is not understandable is how so many liberals can blindly ignore 50 years of evidence to the contrary since then.