The term Darth Dubyous was a reference to the United States President, George W. Bush made by the Baltimore Sun Newspaper due to a line in Star Wars Episode III: Revenge of the Sith in which a character turned evil says "If you're not with me, then you're my enemy!". Bush had previously made a similar statement after the 2001 terrorist attacks, and many people blindly thought this was an intentional reference by George Lucas to Bush. However George Lucas, the father of Star Wars has denied that and noted other world leaders have made similar statements. The line is also found in the Bible spoken by Christ, so the statement is not a exclusive to the President.
http://en.wikipedia.org/wiki/Darth_Dubyous