The closest distance between the United States and Russia occurs at two points:
First, is the distance between Little Diomede Island, Alaska, USA, and Big Diomede Island, Russia, which is only about 2.4 miles or 3.8 kilometers apart.
Secondly, is the Bering Strait, which separates Alaska and Russia, and it is about 53 miles or 85 kilometers wide at its narrowest point.