During the Cold War, Air Force Colonel Harry Shoup was one of the commanders in charge of an early warning radar system based in Colorado.

It had been set up to detect a possible Soviet missile attack on the U.S.

In this animated conversation from our colleagues at StoryCorps, three of Shoup's children recall a surprising phone call their dad received back at 1955.

I remember two phones on his desk. One was this red phone. Only a four-star general at the Pentagon,

and my dad had the number. This was the 50s. This was the Cold War, and he would have been the first one to know if there was an attack on the United States.

So first couple weeks of December in 1955, Dad was at the office, and the red phone rang.

He answered it. This is Colonel Schaup.

And then there was a small voice that just asked, is this Santa Claus?

Dad was very straight-laced, very disciplined. He was annoyed. He was upset. He thought it was a joke.

Yeah, and so now the little voice is crying. And dad realized that it wasn't a joke. So he talked to him,

ho-ho-hoed, and asked if he had been a good boy,

and may I talk to your mother? And the mother got on and said,

you haven't seen the paper yet? There's a phone number to call Santa. It's in the Sears ad.

Dad looked it up, and there it it was his red phone number.

And they had children calling one after another.

So he put a couple airmen on the phones to act like Santa Claus.

It got to be a big joke at the command center.

You know, the old man's really flipped his lid this time.

We're answering Santa calls.

The airmen had this big glass board with the United States on it and Canada, and when airplanes would come in, they would track them.

And Christmas Eve of 1955, when dad walked in, there was a drawing of a sleigh with eight

reindeer coming over the North Pole.

...