The Galactic Tourism Board has warned travelers that Earth can no longer be considered a safe place to visit. “Over the years, many of us have enjoyed our visits to Earth, with its unique opportunities to marvel at their primitive politics, technology, and social habits,” said a spokesbeing for the Board. “Unfortunately, during the past few rotations of the planet, the Earthlings have become unaccountably aggressive. While the reasons for this change of attitude have yet to be determined, it is a sad fact that several visitors to one of Earth’s most fascinatingly dysfunctional societies have recently been assaulted by primitive terrestrial war machines and have lost their lives as a result. Further travel is discouraged. Visitors already in the Sol system are recommended to enjoy some of the other attractions offered by the system, such as a meditation retreat with the peaceful Ice Whales of Europa, or a cloud-tasting party in the Venusian troposphere.”