U.S. Defense Secretary Robert Gates departed Tuesday on his first trip to Latin America to meet top allies. Gates will visit El Salvador, the only Latin American country to still have troops in Iraq, on the trip. Other stops were not made public. Gates, who succeeded Donald Rumsfeld in December, had been scheduled to visit the region in July, with visits planned to Colombia, where Washington has spent billions to fight drug trafficking, and Chile and Peru. But he postponed the trip to stay in Washington as Congress and the White House bitterly debated the Iraq war. The U.S. defense chief is expected to discuss Iraq with Salvadoran President Antonio Saca, whose government reduced its contingent in Iraq from 380 to 280 troops in August.