"The United States and Mexico have a close and complex bilateral relationship. As neighbors and partners under the North American Free Trade Agreement (NAFTA), the United States and Mexico have extensive economic linkages. In recent years, security issues have dominated U.S.- Mexican relations, as the United States has supported Mexican President Felipe Calderón's campaign against organized crime through the Mérida Initiative, an assistance package first funded in FY2008. Immigration and border security have also returned to the forefront of the bilateral agenda since Arizona enacted a strict law against illegal immigration in April 2010. In response to concerns about border security, President Obama deployed 1,200 National Guard troops to support law enforcement efforts along the U.S.-Mexico border in July 2010. […] Congress has appropriated more than $1.5 billion in assistance for Mexico under the Mérida Initiative and expressed concern about the slow delivery of that assistance. In August 2010, Congress approved $600 million in supplemental funds for border security (P.L. 111-230). The 112th Congress is likely to maintain a keen interest in how implementation of the Mérida Initiative and related border security initiatives are proceeding. Congress may consider proposals for comprehensive immigration reform or initiatives aimed at resolving discrete migration or border security issues. On the trade front, Congress is likely to maintain interest in how the Obama Administration moves to resolve ongoing disputes related to trucking and tuna with Mexico and facilitate commerce along the U.S.-Mexico border."
CRS Report for Congress, RL32724