Every few years, someone suggests privatizing the Tennessee Valley Authority. A crucial government corporation, the TVA, among its many other jobs, sells wholesale electricity to local power companies serving 9 million people in parts of seven southeastern states. President Obama floated this idea twice; President Trump proposed the same step in his Very Big Infrastructure Plan earlier this year.

The thinking is that it’s a waste for the government to be in the business of selling wholesale power because private industry could be making more money instead. As long as US senator Lamar Alexander (R-Tennessee) draws breath, though, the TVA won't be sold; he has said the idea is "looney" and has "zero chance of becoming law."

But Alexander won't always be around, and few Americans outside TVA's seven-state footprint likely know or care that it exists. Both the institution and the essential functions that it performs have become invisible. And so, someday, someone will succeed in selling off the TVA.

Much of what government does shares this same curse of invisibility. The unseen, well-functioning systems that allow us to trust our food and water, be confident our bank accounts won’t vanish, and move us seamlessly from place to place are some of the best things that government is capable of. Even as worried Americans on both coasts wring their hands over the daily drumbeat of front page, Trump-led government fiascos, we are at risk of forgetting what government is for—at all levels. The consequences of this collective forgetfulness could be cataclysmic.

Consider the TVA, launched in 1933 as a federal project aimed at harnessing the Tennessee River and developing its valley for the good of the people of a huge region. Nine million Americans live there now (a dramatic increase from the fewer than 5 million who lived there in the 1930s), in portions of Virginia, Kentucky, Alabama, Georgia, North Carolina, and Mississippi, as well as most of Tennessee. In 1947, historian John Gunther called the TVA "the greatest single American invention" of the 20th century and "the biggest contribution the United States has yet made to society in the modern world."

He was right. The TVA transformed one of the poorest areas in the country by making millions of acres of depleted and eroded soil useful for farming, creating a river capable of carrying huge amounts of freight, generating electric power for sale at low prices to retail power companies, stimulating demand for electricity, and developing the local economy in a host of ways—including handing out thousands of books and effectively creating new prosperous towns where thinly-populated, hard-scrabble communities had been barely surviving on land that couldn’t be farmed. Floods in 1937 had made millions of people homeless in the Ohio and Mississippi valleys; by 1942, the TVA's 29 enormous dams made such catastrophes just about impossible in the Tennessee Valley.

Today, TVA makes enough from selling wholesale electricity that it needs no taxpayer funding. And Tennessee Valley residents pay electric rates that are below what more than two-thirds of the country pays. Almost 5 million people get their drinking water from the TVA.

And yet, of course, it probably sounds hopelessly old-fashioned; it was born of the brisk and lively months right after FDR was first elected in 1932, after years when the Great Depression had otherwise flattened American hopes. It was, and is, a regional planning agency.

People in TVA's region don't think of TVA when they flick on a light switch. "There are lots of things that the TVA is doing, but it's not as visible in how it does it," Chattanooga mayor Andy Berke told me recently. "Even when I was growing up, it seemed like there was much more pride in what it had accomplished. It was ours." Over the course of time, for many reasons, TVA has become obscure. And so the necessary public role it continues to play may not be supported the next time someone is looking for a quick reduction in America’s deficit. Privatization, Berke says, "is a perennial idea that just keeps coming back, which to me means that there might be a long-term issue for TVA."

This same disease of obscurity is afflicting the role of government as a whole. A month ago, a graduate student in public administration looked me right in the eye and said, "Why do we need government, anyway? Couldn't the private sector do everything it does, just better?" I wasn't surprised. This kind of technocratic, start-uppy thinking is everywhere.

There is a difference between public sector and private sector values. The whole idea of the public sector is to protect and serve everyone. Only government, for example—and, likely, only local and regional government entities—can carry out long-term, equitable administrative planning for the sea-level rise that is about to swamp coastal US cities. Only government has an interest in protecting everyone, not just the wealthy, from the fires, floods, and tornadoes of changing weather throughout the country. Only government can hope to protect individuals against discrimination by private businesses. And only government is obliged to ensure that the water we drink and the air we breathe are clean.

These functions are just as invisible as electricity. But they, and the role of the government that provides them, need to be protected.

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