Why is there a national helium stockpile?

Helium has other uses apart from lifting dirigibles—and because of its privileged position at one corner of the periodic table, helium will often be the best or only thing to use for a particular purpose.

For example, liquid hydrogen is a very popular rocket fuel. Helium is used as the pressurant gas, i.e., the gas which fills the rocket tank as the fuel is used up and keeps the fuel under pressure. If you didn't have enough helium, what could you use instead—something else that’s a gas at the temperature of liquid hydrogen? I don’t believe there is such a gas.

As technology progresses, we’ll likely find other important uses for helium (again, because of its very special place on the periodic table, and not just in the sense that we’ll likely find other important uses for antimony). In particular if we discover profitable things to do at very low temperatures, helium may be very handy.

Helium is perhaps more easily squandered than any other resource. Discarded steel and rubber goes to the scrap heap and can be recycled. Even the carbon exhaust from used fossil fuels can eventually be captured by plants and made back into fuel again. But vent your waste helium and it flies up to space and is gone forever.

The stockpile is a good idea, not so much because the Nazis might cut off our supply in a war, but because the natural-gas companies might just casually waste the supply for good.

And what’s wrong with lighter-than-air aviation? Like the electric car, the dirigible might make a comeback. Anyway, do we expect our children’s children to get their aerial football coverage from satellite photos?