WASHINGTON (Reuters) - President Barack Obama said on Friday after meeting with Mexican President Enrique Pena Nieto that Mexico is a critical partner to the United States on a host of issues, including security and climate change. “I am proud of what we’ve achieved together,” Obama told the Mexican leader, noting that with the heated rhetoric of the U.S. presidential election campaign, Mexico’s importance to the United States as a major trading partner and neighbor is often not acknowledged.  