The United States' interest in policing its own backyard should be self-evident. Ever since President Monroe's declaration warning the European powers that the US would look unkindly upon their colonial escapades in Latin America (later called the "Monroe Doctrine"), the US has maintained vigilance over the actions of outside nations in Latin America and has also taken action to protect itself against threats from the South.
The Robert Novak column that Wongdoes linked below notes that there is a new threat to the United States and it is growing daily: the Hugo Chavez dictatorship in Venezuela. From the US failure to condemn the fraudulent Chavez retention election outcome last year to the Bush Administration's seeming ignorance of, or ignoring, Chavez's work with the FARC cocaine-running rebels in Colombia, the situation is getting progressively worse.
The Bush Administration has failed to take sufficient action against this communist totalitarian oil-funded dictator to our south, and has not been forceful with Chavez in the least. The Bush Administration also never sufficiently pushed for the appointment of Otto Reich to the State Department post it nominated him for in 2001 -- Bush withdrew the nomination primarily due to the strong opposition by Chris Dodd and John Kerry. Those Senators hated Reich because he befriended the Contras in the 1980s, denounced the communist Ortega (whom Kerry and Dodd loved) and was PROIVEN RIGHT in 1990 when the Nicaraguans had free elections and dumped their Sandinista slave-masters out of office.
Chavez hailed the Iraqi insurgents, makes common cause with Castro and is destabilizing the region to a degree that Castro and Daniel Ortega had only dreamed of reaching. Bush needs to clamp down on this man and make certain that Chavez knows that Stalinist insurgency and terrorist support under the US's own nose will not be tolerated.