"Over the past six years, American energy companies have sent more coal than ever to other parts of the world, in some cases to places with more lax environmental standards."

"The U.S. in 2012 accounted for 9 percent of worldwide coal exports, the latest data available." 

It increases each year.  "Last year, Germany's carbon dioxide emissions grew by 1.2 percent, in large part because the country burned more coal."

What happens in any part of the world has an effect in our part of the world.  Maybe it'd be better to burn coal here with modern facilities and not ship our energy.  Then too consider the emissions from the act of shipping.