From: John D. Howard
Date: 2015 Aug 15, 10:15 -0700
Because the GPS system was a US military system it was set up to reflect the needs of the US military. I used the the GPS system in the early 1980's. When you set up a GLICM (ground launched cruse missle) to hit Moscow no one was worried where the Greenwitch Observtory was. Now that GPS is the de facto nav system that everyone uses it is easier to move the prime meridian than the GPS.