Members of the community hold hands in April in front of police officers in riot gear outside a CVS store that was looted and burned in Baltimore. (REUTERS/Jim Bourg)

Shortly after Baltimore erupted in riots this spring, forcing a public reckoning with the many ways American society has denied opportunity to blacks, a counter-meme emerged among some conservatives. The Baltimore school district, they argued, spends more lavishly on its students — $15,287 per pupil — than just about any other community in the country. So how can there still be structural disadvantage or lingering racism in a city that spends so much on its poor black kids?

There are several flaws in this argument. Baltimore ranks among the country's top spenders if you compare it only to the 100 largest, and mostly urban, school districts in the U.S. It's hardly the most lavish compared to smaller, wealthier districts that don't make this list (and that drive disparities between urban and suburban schools). And a lot of the money a district like Baltimore gets goes to the expenses unique to high-poverty schools, like free lunch and drop-out prevention programs.

The main problem with this argument, though, is that it involves a much larger misunderstanding of history. It assumes that decades of institutional racism and inequality designed into all realms of life in a city like Baltimore — in the school system, the transportation network, the housing market, the criminal justice system, the lending industry, the job market, the air — might be fixed by $15,287 per pupil in spending today, if it were just well-spent.

In fact, the historical problem in Baltimore — and in Milwaukee, and in Cleveland, and other placesis much larger than the small-bore programs or even school spending that we've thrown at it. And its effects have stayed with us even as overt racism largely has not. This is the key point Barack Obama made in comments on the comedian Marc Maron's podcast that aired Monday morning:

The legacy of slavery, Jim Crow, discrimination in almost every institution of our lives — that casts a long shadow, and that’s still part of our DNA that’s passed on. We’re not cured of it — racism, we are not cured of it. It’s not just a matter of it not being polite to say ‘nigger’ in public. That’s not the measure of whether racism still exists or not. It’s not just a matter of overt discrimination. Societies don’t overnight completely erase everything that happened 2-300 years prior.

This racism and racial inequality has been fostered not just by individual bias, but by institutions of power. And this second kind of discrimination recedes much more slowly.

It's rooted in public schools, where black children are six times more likely than white children to go to schools with high poverty rates:

It's rooted in the lending market, where lawsuits and federal complaints continue to finger banks for predatory lending and redlining in black communities. The legacy of these practices is apparent in persistently lower black homeownership rates:

Much of the family wealth in America comes from housing. And so those lower homeownership rates — which date all the way back to a time when the Federal Housing Administration refused to back mortgages to blacks — have directly translated to lower black wealth:

2013 dollars. Sources: Urban Institute calculations from Survey of Financial Characteristics of Consumers 1962, Survey of Changes in Family Finances 1963, Survey of Consumer Finances 1983-2013. Urban Institute

Discrimination exists in the criminal justice system, where the incarceration rate for blacks in the era of the drug war has spiked far beyond the rate for whites:

Discrimination has been rooted, too, in American elections, in which blacks — until the 2012 presidential election — have historically remained less likely to vote than whites:

It has taken decades for black political participation to equal whites, and for their low participation particularly in the South to catch up to the rest of the country (Census data doesn't go back farther than 1964, when these disparities were no doubt even wider). Notably, since black voter participation surpassed whites in 2012, many states have passed new voter laws that experts argue will have the effect of suppressing black participation again.

These are the central institutions in American society — banks, courts, prisons, elections, schools, government itself — that have "cast a long shadow" as Obama puts it, on life in black communities today. These are the things we can't erase overnight, even as we efface certain racist vocabulary — or even racist symbols — from society.