By Alister Bull and Matt Spetalnick
SAN SALVADOR (Reuters) - President Barack Obama headed home from El Salvador on Wednesday, wrapping up a five-day visit to Latin America after receiving a briefing on the U.S.-led military action in Libya that has overshadowed his tour.
The president cut short his trip by several hours to return to Washington, where he will face critics of U.S. involvement in the international air campaign against Libyan leader Muammar Gaddafi.
Critics worry about the clarity of the U.S. role in the Libyan mission, its goals and the cost of entanglement in a third Muslim country while U.S. troops remain in Iraq and Afghanistan.
Obama ordered the military action after starting his trip in Brazil, and his aides have scrambled to keep him abreast of events during an event-packed schedule designed to reassert U.S. influence in a fast-growing region where China has become a powerful rival.
In economic powerhouse Brazil and Chile, Obama sought investment opportunities and pushed for U.S. exports that would boost hiring back home, where high unemployment will be a vital factor in his 2012 reelection hopes.
In tiny, impoverished El Salvador, Obama switched themes to focus on immigration and security, promising $200 million to help Central America fight narco gangs whose violence has spilled across the U.S.-Mexico border.
The El Salvador stop wrapped up a five-day mission to re-engage with a region where Washington's approach has ranged from heavy-handed use of power for much of the 20th century to one of neglect in recent years.
Obama's trip was seen to have helped reinforce hemispheric ties but the Libya attacks did not go down well with most of Latin America and he delivered no major breakthroughs on long-promised trade pacts or key trade disputes.
Obama's travels were dogged by concern over the Western air campaign over Libya. He is struggling to balance handling world crises with his domestic priorities of jobs and economic recovery, considered crucial to his 2012 re-election chances.
He mostly stuck to his travel plans even as aides scrambled to keep him up to speed on Libyan developments and unrest in the Arab world.
(Editing by John Whitesides)