US President Barack Obama came to Colombia hoping to defend US trade interests in Latin America. Instead, he found himself isolated on Cuba, and faced with a Secret Service sex scandal.

Pressure from his counterparts at the Summit of the Americas in Cartagena to do more than just compliment their “remarkable” progress and bring Cuba back into the regional fold left Obama slightly on the back foot.

His refusal to budge on America’s long-time foe prevented the leaders from signing a final statement Sunday, after Colombian President Juan Manuel Santos, Washington’s closest ally in Latin America, said it would be “unacceptable” to keep Cuba out of the next gathering.

Brazilian President Dilma Rousseff meanwhile urged Washington to treat its regional partners as “equals,” showing that Latin American leaders are growing more confident — or that the United States is losing influence in its own backyard.

Treading cautiously less than seven months before he seeks re-election, especially with likely Republican foe Mitt Romney repeatedly accusing him of apologizing for America, Obama can nonetheless come home with one feather in his cap — a US-Colombia free trade agreement lowering duties on US exports.

The deal, which will come into force on May 15, came after Obama vowed Friday that he would help shore up the sour US economy with increased cooperation in a region that absorbs 40 percent of his country’s exports.

But at home, the summit is far more likely to be remembered for the scandal — 11 Secret Service and five military personnel were pulled from duty amid claims the men brought prostitutes to their hotel rooms in Cartagena.

The incident involving the very agency tasked with the president’s security overshadowed the summit and prompted the White House to insist that Obama remained focused on his official program.

Representative Darrell Issa, chairman of the House Oversight Committee, warned that more agents could be involved in the sex scandal and suggested the Secret Service may need some “soul-searching” after the embarrassing incident.

White House spokesman Jay Carney has said Obama had full confidence in the Secret Service and that the incident had no impact on the president’s security.

The meetings in Cartagena were not the first time embarrassing incidents at summits had trumped substance for the Democratic incumbent.

On the sidelines of a nuclear security summit in Seoul, Obama was heard on an open mic privately explaining to President Dmitry Medvedev that he had little flexibility to address Russia’s objections to a US missile defense shield before his reelection bid.

The exchange appeared to indicate that Obama believes he has little leverage to conclude deeply divisive foreign policy election issues in a campaign year — and also that he is confident he will win reelection.

And at November’s G20 meet in Cannes, Obama was heard complaining to French President Nicolas Sarkozy that he had to deal with Israeli Prime Minister Benjamin Netanyahu “every day.”

Sarkozy also said he couldn’t stand “liar” Netanyahu, amid criticism of the ongoing building of Jewish settlements on occupied Palestinian land.