On November 13, 2007, the European Parliment voted to go ahead with a plan to cap carbon dioxide emissions for all aircraft operating to or from EU airports.  Airlines may trade pollution credits like other industries do now, but the gist of the rule is that aircraft operators must clean up and reduce emissions.  The US Environmental Protection Agency has received a petition from several environmental organizations and states demanding regulation of aircraft emissions, similar to the EU plan.  What are the ramifications of such regulation?