[There were a LOT of nuclear tests in America, on American soil, mostly in Nevada. There have been all kinds of nuclear tests, in the air, at sea, in space, underground, etc. Scientists, especially American scientists, tested and measured nuclear explosions under every conceivable kind of condition. In the final years, underground nuclear testing was the most common and safe way to do it. Atmospheric tests were the most dangerous because of winds. Jan]
Here’s the video: https://www.youtube.com/watch?v=FCf_yEoLj9o