YANGON, Myanmar — Barack Obama was riding in his motorcade, the first U.S. president ever to visit long-isolated Myanmar, when he suddenly ordered an unscheduled detour Monday.

The Secret Service scrambled. Police raced ahead to clear crowded roads. Tourists were chased away.

Soon Obama and Secretary of State Hillary Rodham Clinton were barefoot in the muggy afternoon. They hiked up a long set of marble stairs and took in the 325-foot-tall Shwedagon Pagoda, which is covered with gold leaf and topped by a jewel-encrusted spire. It is the oldest Buddhist pagoda in the world and the most revered site in this overwhelmingly Buddhist nation.

After consulting a guide, Obama walked over to a statue for those born on Fridays, which he was. Tradition calls for pouring a cup of water over the Buddha's shoulder once for each year of age, plus one, to douse the "human flames" of emotion that cause suffering. Obama is 51. "I'm going to do it 11 times," he announced. No one complained.

After finishing, Obama turned to reporters and explained. "I was dousing 11 flames." Known as a Mr. Cool, he offered anger as an example. The guide named a few others, including lust and hatred.

So went a whirlwind day for a president who showed himself willing to set aside the bloodshed in the Middle East, the fiscal cliff back home, and other crises to mix tourism with diplomacy for a few hours in a nation struggling to emerge from decades of oppressive military rule.

He met with President Thein Sein, once viewed as a roadblock to democratic reform, who vowed to follow Obama's campaign slogan — Forward! He visited Aung San Suu Kyi, the fellow Nobel laureate and iconic dissident turned politician, at the lovely lakeside home that was her prison for 15 years, a scene almost unimaginable not long ago. He met with civil-society activists and opposition-party leaders. He spoke at a university. All in six hours.

Obama offered an explicit path ahead when he addressed a crowd of about 1,500 people at a dilapidated and sooty university building that was once a hotbed of political protest.

Obama said Myanmar, also known as Burma, "must" pursue democratic institutions, and he challenged the government to work toward unification and civil rights. Obama, who rarely talks about his race, drew a direct line to his personal experience.

"I stand before you today as president of the most powerful nation on Earth, but recognizing that once the color of my skin would have denied me the right to vote," he said.

Obama spent part of his childhood in Indonesia, where his mother was an anthropologist, and Obama clearly enjoyed being back in Southeast Asia. Rich with natural resources, Myanmar is part of the administration's efforts to embrace engagement as part of his foreign policy and to check China's influence in its own backyard.

Obama's stop in Myanmar was bookended by trips to Thailand and Cambodia, both also wary of China's growing ambitions.

Human-rights activists have argued that Obama's visit is too much too soon, noting that Thein Sein's government still detains political prisoners, fails to recognize citizenship for a minority group and has yet to fully embrace democracy. In response, both the White House and Thein Sein were careful to push a message of progress and goodwill.

Obama's motorcade cruised past thousands of supporters who crowded the streets and chanted his name to reach Suu Kyi's large home. The garden was spruced up with new rose bushes and freshly planted flowers for the occasion.

The soft-spoken Suu Kyi warned of the dangers of being "lured by a mirage of success." She urged Obama to apply continued pressure on Thein Sein's government.