Uranium probably always will be a critical material no matter how much of a supply the U.S. has because it is the only naturally-occurring fissile element on earth. It has no real satisfactory replacement for what it can do. The U.S. is importing over 90 percent of its uranium needs from a dozen countries around the world. Worse, it is over-reliant on Russia and two of its former satellite countries, Kazakhstan and Uzbekistan, for more than 40 percent of those imports