Manganese is an essential nutrient. You have to have it in your food in order for your body to function properly. That being said, instances of manganese deficiency are rare. This particular trace element is found in sufficient amounts in a wide variety of foodstuffs, everything from nuts to grains to vegetables and fruits. It would be hard not to get the 1-2 milligrams per day you need just from ordinary eating.

Manganese, like many metals, is toxic in larger quantities. People who are exposed to manganese in the workplace—mostly welders—have to take precautions. Manganese is a crucial ingredient in the production of stainless steel. In fact, there are few substitutes for manganese in its metallurgical applications.

So why should we care about manganese? Clearly it has enormous industrial importance. Without steel there is no modern world! The other reason we should care is that there is no domestic production of manganese in the United States.

We import ALL of the manganese we use in this country. It comes from places like South Africa, Brazil, Gabon, Ukraine, India, and China. There are probably billions of tons of manganese on the seafloor in the form of nodules, but no one has figured out how to mine that stuff. Known deposits here in the States are too low-grade and extraction costs too high to be an alternative.

That means we have to depend on other countries for a critical mineral.

It’s not the only one. Vanadium—another significant ingredient in steel—is entirely imported. So are tantalum, indium, gallium, cesium, fluorspar, asbestos, niobium, arsenic, rubidium, and several other important industrial materials.

We live on this great big rock. The spot we live has a lot of good stuff. But not all the stuff we need. That means we need other people.

There is no such thing as “self-sufficiency.” It is one of those nice notions that gets kicked around by romantics, back-to-the land types, politicos, and ill-informed pundits (are there other kinds?). Humans are a social species. We live in a web of inter-connections. Without each other, that is, without society, we cannot survive. Civilization may be a relatively recent thing in human history, but society is not. The first humans lived in groups and depended on each other, the last humans will as well.

It’s OK to re-watch Jeremiah Johnson and marvel at the independence and self-sufficiency of those old mountain men, but stop and think a little. All those guys had rifles and cartridges. It takes an industrial base to manufacture such things. All those guys had horses and pack animals. Those are the fruits of a well-developed agrarian economy. Jeremiah and his pals may have been tough and smart, but they couldn’t have done shit without steel and animal breeding. And those are just the first two things that come to mind.

If you want to “shop local” and “buy American” because you want to do right by your neighbors, I say good on you. I try to do that. Even if they are selling Japanese cars made in Mexico!