Another revelation has come to light surrounding the nature of U.S. spying programs as the G8 summit kicks off in Ireland. A document disclosed by Edward Snowden, the leaker of the N.S.A. surveillance programs, reveals that American and British intelligence agencies eavesdropped on world leaders at 2009 conferences in London. The document shows that the emails and phone calls of representatives from other countries were monitored, and the communications of then-Russian president Dmitri Medvedev were intercepted by the United States. Scott Shane, national security correspondent for our partner The New York Times, explains how this will affect the G8 summit and U.S. diplomatic relations.