Google scrambling sensitive map information?

Cyphoid writes: While viewing my university (the University of Massachusetts Lowell) with Google Maps, I noticed a select portion of the campus that was pixelated. Incidentally, the building and the water tower looking structure that was pixelated happens to be the operational nuclear research facility on campus. Curious, I attempted to view the Pilgrim Nuclear Power Plant in Plymouth, Massachusetts, which led to another pixelated section of earth. What or who is compelling Google to selectively smudge out these images? Is there something that Google is being told about our nation's security that we are not? Will all satellite images of facilities that the government deems as "sensitive" soon be subject to censoring?