Obama landed at Havana's Jose Marti International Airport aboard Air Force One, the presidential jet with "United States of America" emblazoned across its fuselage, a sight almost unimaginable not long ago.
Stepping down onto the red carpet in a light drizzle, Obama and his family, smiling broadly and with umbrellas in hand, were greeted by Cuban Foreign Minister Bruno Rodriguez. They then boarded a black armored limousine, with U.S. and Cuban flags fluttering from the hood, and headed out in their motorcade.
The three-day trip, the first by a U.S. president to Cuba in 88 years, is the culmination of a diplomatic opening announced by Obama and Cuban President Raul Castro in December 2014, ending a Cold War-era estrangement that began when the Cuban revolution ousted a pro-American government in 1959.
Obama, who abandoned a longtime U.S. policy of trying to isolate Cuba, wants to make his shift irreversible. But major obstacles remain to full normalization of ties, and the Democratic president's critics at home say the visit is premature.
Traveling with first lady Michelle Obama, her mother and their daughters, Sasha and Malia, the president was to visit the newly reopened U.S. Embassy and then play tourist on his first night on the Caribbean island, taking in the sights of Old Havana.
He will hold talks with Raul Castro – but not his brother Fidel, the revolutionary leader - and speak to entrepreneurs on Monday. He meets privately with dissidents, addresses Cubans live on state-run media and attends an exhibition baseball game on Tuesday.
SYMBOLISM AND SUBSTANCE
The trip carries both symbolism and substance after decades of hostility between Washington and Havana.
It makes Obama the first sitting American president to visit Cuba since Calvin Coolidge arrived on a battleship in 1928.
It is also another major step in chipping away at remaining barriers to U.S.-Cuba trade and travel and developing more normal relations between Washington and Havana.
Since rapprochement, the two sides have restored diplomatic ties and signed commercial deals on telecommunications and scheduled airline service.
Major differences remain, notably the 54-year-old economic embargo of Cuba. Obama has asked Congress to rescind it, but the move has been blocked by the Republican leadership.
Underscoring the ideological divide that persists between Washington and Havana, Cuban police, backed by hundreds of pro-government demonstrators, broke up the regular march of a leading dissident group, the Ladies in White, detaining about 50 people just hours before Obama arrived.
Plainclothes police blanketed the capital with security, while public works crews busily laid down asphalt in a city where drivers joke they must navigate "potholes with streets."
Welcome signs with images of Obama alongside Raul Castro popped up in colonial Old Havana, which the president and his family will tour later on Sunday. Obama has used executive authority to loosen trade and travel restrictions to advance his outreach to Cuba, one of his top foreign policy priorities along with the Iran nuclear deal.
But Cuba still complains about the occupation of the naval base at Guantanamo Bay, which Obama has said is not up for discussion, as well as U.S. support for dissidents and anti-communist radio and TV programs beamed into Cuba.
Speaking to reporters, Foreign Trade and Foreign Investment minister Rodrigo Malmierca Díaz said Obama's regulatory moves "go in the right direction." But he added: "We can’t reach a normalization of relations with the blockade still in effect and without resolving other themes of high importance."
MAKING ENGAGEMENT IRREVERSIBLE
The Americans in turn criticize one-party rule and repression of political opponents, an issue that aides said Obama would address publicly and privately.
The Ladies in White and their male supporters protested after a Palm Sunday service and were pulled into police vans after they sat down to block a street. A similar scene plays out every Sunday, but this time it was more intense than usual. The government dismisses the dissidents, who are funded by U.S. interests, as mercenaries seeking to destabilize the country.
Obama's critics at home accuse him of making too many concessions for too little in return from the Cuban government and of using his trip to take an unearned "victory lap." But Obama's more practical goal is to do everything he can to make sure his Cuba engagement cannot be rolled back, even if a Republican wins the White House in the Nov. 8 election.
Although general U.S. tourism to the island is still officially banned under the embargo, a sign of changing times was the presence of groups of U.S. travelers marveling at the vintage American cars rumbling through the streets.
Little progress on the main issues is expected when Obama and Castro meet on Monday or at a state dinner that evening.
Instead, the highlights are likely to be Obama's speech on live Cuban television on Tuesday, when he will also meet dissidents and attend an exhibition baseball game between Major League Baseball's Tampa Bay Rays and Cuba's national team.
Underlining Obama’s political challenge at home, the office of U.S. Representative Ed Royce, Republican chairman of the House Foreign Affairs Committee, said the president’s policy "has only served to prop up the communist Castro regime.”