Calls to shut down information sources are once again being heard, this time after it was revealed that four terror suspects used Google Earth to allegedly research the terrain at a US airport. 

Apparently Abdul Kadir, accused of plotting to blow up parts of New York's JFK International Airport, told his co-accused to get images of the site from Google Earth.
This revelation has raised concerns about the publication of potentially-sensitive information on the Internet and comes just weeks after the last call to censor satellite images.
It's not the first time suspected terrorists have used Google Earth to pinpoint sites for their attacks, according to those calling for an end to freely vailable imagery.
Google counters that the images are widely available from numerous sources and, anyway, its own images are anything from three to six months old.
Should some countries decide on a ban, there is some doubt as to how it could be implemented around the world.