The environmental picture is much brighter for the United States in 2013 than in 1970, the year the U.S. Environmental Protection Agency debuted. Writing for Commentary magazine’s website, John Steele Gordon addresses a puzzling fact about the EPA’s willingness to publicize its success.

In 1970 31 million tons of sulphur dioxide, a prime contributor to smog, was emitted into the atmosphere. In 2008 it was 11 million tons. In 1970 34 million tons of volatile organic compounds were emitted. In 2008 it was 16 million. In 1970 204 million tons of carbon monoxide; in 2008 it was 72 million. The EPA recently declared carbon dioxide a pollutant (which means we pollute the atmosphere every time we exhale). And the only major country in the world where carbon dioxide emissions are declining? The United States. We emitted less CO2 in 2012 than in 1992. Water pollution has similarly abated. Unhealthy air days in major U.S. cities these days are a rarity. Even Los Angeles had only 18 in all of 2011. Manhattan had exactly none.

And this despite the fact that the population of the country has doubled, the GDP has more than tripled in real terms, and the number of cars and trucks hugely increased.

You would think that the EPA would want to highlight the tremendous progress that’s been made over its bureaucratic lifetime. But try to winkle the statistics out of its website. They either aren’t there, or they are hard to find, or they are incomplete, or they hard to compare with each other.

Why would this be? Simple: Bureaucracies want to manage problems not solve them. Solving the problem a bureaucracy was created to handle might have an adverse impact on its funding, and bureaucracies measure their prestige by the size of their budgets. So success, in effect, is bad news for bureaucrats.

Likewise, the various environmental organizations are at great pains to not tout how much progress has been achieved. That might cause people to put away their checkbooks.

As a result, one of the great American success stories of the last 40 years—just how clean the American environment is getting—is hidden from sight.