The blazing Caribbean sun rose Saturday on a U.S. flag flying over Havana for the first time in 54 years and people discussing political reform with an openness that once would have been unimaginable in Cuba.

Speaking before the raising of the Stars and Stripes at the newly reopened U.S. Embassy, Secretary of State John Kerry called for systemic political change on the island, a topic that remains taboo here despite a series of economic reforms and the re-establishment last month of diplomatic ties severed during the Cold War.

“We remain convinced the people of Cuba would be best served by genuine democracy, where people are free to choose their leaders,” Kerry said, going on to call for responsive institutions and independent civil society in this single-party state.