The topic du jour on the left these days is inequality. But why does the left care about inequality? Do they really want to lift those at the bottom of the income ladder? Or are they just looking for one more reason to increase the power of government?

If you care about those at the bottom then you are wasting your time and everyone else’s time unless you focus on one and only one phenomenon: the inequality of educational opportunity. Poor kids are almost always enrolled in bad schools. Rich kids are almost always in good schools.

So what does the left have to say about the public school system? Almost nothing. Nothing? That’s right. Nothing. I can’t remember ever seeing an editorial by Paul Krugman on how to reform the public schools. So I Googled to see if I have missed something. The only thing I found was a negative post about vouchers. And Krugman is not alone.

You almost never see anything written by left-of-center folks on reforming the public schools. And I have noticed on TV talk shows that it’s almost impossible to get liberals to agree to the most modest of all reform ideas: getting rid of bad teachers and making sure we keep the good ones.

Here is the uncomfortable reality:

1. Our system of public education is one of the most regressive features of American society.

2. There is almost nothing we could do that would be more impactful in reducing inequality of educational opportunity and inequality overall than to do what Sweden has done: give every child a voucher and let them select a school of choice.

3. Yet on the left there is almost uniform resistance to this idea or any other idea that challenges the power of the teachers unions.

Over and over again, liberal pundits come up with objections to the idea of school choice. What they completely ignore is that we already have a system of school choice.

How school choice currently works. The vast majority of parents are already participating in a system of school choice. For example, there are 79 school districts within a 50-mile radius of downtown Dallas. Assuming each district has at least two campuses at each grade level, a typical family has a choice of about 158 public schools – provided the parents can afford to buy a house in any neighborhood and are willing to drive a considerable distance to work.

How well does this system work? Better than you might think. A study by researchers at Southern Methodist University and the Dallas Federal Reserve Bank found that North Dallas houses near higher-ranking elementary schools sold for about 20 percent more than houses near lower-ranking schools. The authors conclude that the market for education works surprisingly well. Parents can discern quality and the market charges a premium for it.

This conclusion is supported by an informal survey conducted by Dallas attorney H. Martin Gibson of housing prices in Highland Park – a wealthy Dallas suburb. Although most Highland Park homes are inside the Highland Park Independent School District (HPISD), a few are in the Dallas Independent School District (DISD). Gibson found that, all else equal, homes on the HPISD side of the street sell for 24 percent more than those on the DISD side. This implies that many Highland Park homeowners are paying about $72,000 just for the right to send their children to Highland Park schools.

More recently, the Brookings Institution investigated the same phenomena nationwide:

• Across the 100 largest metropolitan areas, housing costs an average of 2.4 times as much, or nearly $11,000 more per year, near a high-scoring public school than near a low-scoring public school.

• This housing cost gap reflects that home values are $205,000 higher on average in the neighborhoods of high-scoring versus low-scoring schools. Near high-scoring schools, typical homes have 1.5 additional rooms and the share of housing units that are rented is roughly 30 percentage points lower than in neighborhoods near low-scoring schools.

If the system works well for those who have money, how does it work for those who don’t? What happens to families who cannot afford to buy a house in an expensive neighborhood? Unfortunately, they’re out of luck. Since the current choice system in Dallas and across the country rations educational opportunity through the housing market, it’s almost inevitable that the children of low-income families will end up in schools no one else wants to attend. These are the schools with the worst teachers, the worst principals and the lowest test scores.

A compounding factor is that parents who can afford more expensive homes are much more adept at dealing with public sector bureaucracies. If a bad teacher or principal is identified at a school in a wealthy neighborhood, parents typically will complain until that person is transferred to another school. Then the parents at the next school will likely complain. This transfer process will continue until the worst teachers and worst principals wind up at schools where either the parents don’t complain or nothing happens if they do. These invariably are schools in low-income neighborhoods.

Of course, it is possible to turn a truly bad school into a good one through some Herculean effort. But if the effort was successful and perceived to be permanent, “gentrification” would occur. Middle-income families would move into the neighborhood and bid up housing prices. Low-income residents would be priced out of the market and would have to move somewhere else. It is no accident that the worst schools are consistently found in low-income neighborhoods that lie predominantly in urban areas. Indeed, it could not be otherwise.

How liberals view school choice. There have always been some on the left who want to liberate poor children from bad schools. But, sad to say, they are in a distinct minority. Here is Krugman on school choice:

… [P]roposals for school vouchers should be critiqued not only on educational or cost-efficiency grounds but also because they raise the risk of a collapse in the political support for public education. (If upper-middle-class families are allowed to “top up” their vouchers with their own money, they will soon realize that it is in their interest to cut the size of the vouchers as much as possible). And-dare we say it?-we should in general oppose privatization plans if they are likely to destroy public sector unions. After all, people on the right tend to favor privatization for exactly the same reason.

And what exactly would be wrong if the teachers unions went away? Clearly they view the schools as a jobs program far more than a way of lifting children out of poverty. What the teachers unions do systematically is support big government. They want higher taxes and more government spending. Even if you thought that these were good things, is it worth it to sacrifice millions of poor children in the process? The left apparently thinks so.

Postscript: Newly elected New York City Mayor Bill De Blasio appeared on Morning Joe the other day to explain why he wants to close some of the city’s best charter schools:

Among the 870 Success Academy seats blocked was a modest 194-student expansion for Success Academy students in Harlem to move into a new middle school. That triggered days of searing press coverage pointing out that those 194 students, all low-income minorities, were coming from a school, Success Academy 4, that killed it on the new state test scores, with 80 percent of the students passing the math test, and 59 percent the English test. The co-located middle school the mayor is protecting and where many of those 194 charter students would end up: P.S. 149, where 5 percent of students passed the math test, and 11 percent the English test. (Slate)

While the other guests rightly pound on the mayor and expressed outrage, Economist Jeffrey Sachs sat by and said nothing. And everyone has a right to be silent. But not if you intend to turn around and tell us how important it is to do something about inequality.