National Geographic: As President Obama visits upstate New York and northeastern Pennsylvania this week to discuss his education agenda, a separate issue looms large in the background: fracking, a practice that has transformed Pennsylvania's economy and divided New York, where a moratorium is in place.
Protesters on both sides of the issue are expected to greet the President. And while his trip highlights many unresolved issues related to America's new wealth of natural gas and oil, a growing number of communities...