Following is a transcript of the video. Narrator: During the Cold War, the US government built numerous missile silos in secret locations across the country. Many sit empty and useless today.
The completion of 20 new missile silos for the Ground-Based Midcourse Defense system at Fort Greely, Alaska, comes amid a new look at its modernization.
North Korea has acquired the ability to attack anywhere in the U.S. mainland with intercontinental ballistic missiles.