Who developed the first nuclear submarine?

The first operational nuclear submarine, the USS Nautilus(SSN-571), was developed by the United States. The idea of a submarine dates far back in history, but the technology required to actually build an operational undersea boat is relatively new. Applying nuclear power to this concept is newer still, and it had to wait until nuclear power could be harnessed in the form of a safe and reliable nuclear reactor. A link can be found below for more information.