Hey, this is Outside In. I'm Nate Hedgy.

Now, if you had told me even three years ago that the U.S. would be threatening to invade Greenland,

I think you were kind of kooky.

But here we are.

President Trump has his eye on the world's largest island, so much so that he sent his vice president there to give a speech, albeit on a U.S. military base.

How we doing?

It's cold as shit here.

Nobody's talking.

Trump says he wants Greenland for national security reasons, and because of its wealth of resources.

Oil, natural gas, and rare earth minerals, all buried under the ice.

But if you know your history, you know that this

isn't the first time that the U.S. has been interested in these things. A few years ago,

producer Daniel Ackerman brought us a story that I have been thinking of a lot

lately. It's about a tube of frozen water that helped unlock the planet's hidden climate history.

But it's also about security, the Cold War, and Greenland as a sometimes unwilling participant in

global geopolitics.

So we've brushed the snow off this one, and let me tell you, it is really a wild story.

Stay tuned. All right, let's start with the tape.

On the top of the world, below the surface of a giant ice cap, a city is buried.

This isn't from James Bond or the Marvel comic universe.

This is a documentary made in the 1960s by the U.S. Department of Defense.

The United States Army has established an unprecedented nuclear-powered Arctic research center.

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