"UFOs" author Leslie Kean joins "Tucker Carlson Tonight" to discuss why the United States government has "covered up" UFO information for decades.

LESLIE KEAN: It’s such a big and complex question, Tucker. The coverup, if you want to call it a coverup, began in the ‘40s, 50s, ‘60s during the Cold War. So there was a lot of concern because we were dealing with Russians. You know, they didn’t want things to get mixed up with all the issues of Russian aircraft and all the issues within the Cold War. I think there has been a concern what to tell people when you can't explain something. There's something operating with impunity that shows advanced technology. What do you tell people about that when you can’t stop it when you can't explain it?

I think there's also a stigma, Tucker, that you are aware of. You have been one of those people battling this stigma where it's just been considered for decades and decades to be something ridiculous. People don’t want to talk about something that's going to make them look ridiculous or even damage their careers. So there are so many factors that kept this under wraps, and we're really at an important time right now. I am so happy to see it changing after all of these years.

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