Earlier this year, a 51-year-old Mexican man named Isidro Baldenegro López was shot to death in Mexico’s Chihuahua state. Mr. López was a well-known environmental activist and advocate for the indigenous Tarahumara people. For years he had campaigned against the deforestation of old growth pine-oak forests in the Sierra Madre range - even winning the prestigious Goldman Environmental Prize in 2005. Unfortunately it’s just one of a large and growing number of cases of environmental activists