Just a year after his administration signaled it would help Burma emerge from decades of repressive military rule, President Obama will make history Monday by becoming the first U.S. president to visit the long-isolated Southeast Asian nation.

Obama’s gesture, the centerpiece of a four-day trip to the region that will include stops in Thailand and Cambodia, comes as the White House seeks to send another strong message that it is serious about its “pivot to Asia” — a rebalancing of U.S. military and economic interests after more than a decade of war in the Middle East.

During his six hours in Burma, Obama is scheduled to meet separately with President Thein Sein and democracy leader Aung San Suu Kyi, whose release in 2010 following 15 years under house arrest launched her nation’s opening to the West. She has since become a member of parliament.

Administration officials said Obama intends to hail the country’s “remarkable progress” toward democratic rule during a speech at Rangoon University in Burma’s historic capital but also to push its leaders farther along the path of reform, mindful that the nascent effort remains fragile.

“We are not naive to this. We understand the dangers of backsliding, and if it happens, we’ll take note of it,” the White House national security adviser, Thomas E. Donilon, said in Washington on Thursday. “There’s a lot more work to do, but it’s a moment when the president really can attempt to lock in the progress that has been made and give a tremendous boost to the reform movement in Burma.”

Buffeted by criticism of its Middle East policy after recent setbacks to the Arab Spring democracy movement, the administration hopes the president’s visit to Southeast Asia will jump-start his second-term foreign policy agenda as the United States seeks to counterbalance China’s growing influence.

Obama will meet with Thailand’s prime minister, Yingluck Shinawatra, and in Cambodia he will attend a gathering of the Association of Southeast Asian Nations and participate in this year’s East Asia Summit to discuss security issues. The president is also expected to meet privately with several foreign leaders, including Chinese Premier Wen Jiabao and Japanese Prime Minister Yoshihiko Noda.

Ben Rhodes, the deputy national security adviser for strategic communication, called the renewed Asia focus a “critical part of the president’s second term and ultimately his foreign policy legacy.” He added, “We see this as an opportunity to dramatically increase U.S. exports and to increase U.S. leadership in the fastest-growing part of the world.”

But in betting on Burma, where the United States installed a new ambassador in June for the first time in more than two decades, the White House has opened itself to criticism that it is taking a victory lap on Asia too quickly. Leading human rights organizations have lobbied hard against Obama’s visits Burma and Cambodia because of what they say are ongoing abuses by their governments.

In Burma, the activists cite ethnic violence against the Muslim minority that has left hundreds dead and up to 100,000 people displaced, as well as an estimated 200 political activists in jail and continued military corruption. They warn that the Obama administration is rewarding the government for modest reforms without any tangible new commitments to show for it.

“They believe in the magical power of an event and an address,” said John Sifton, Asia advocacy director at Human Rights Watch. “But this trip is premature and undeserved. Why are they going? I do not know a legitimate reason. They’re going and reinforcing a message that rewards them for something they’ve already been rewarded for.”

The White House launched the Asia focus a year ago, highlighted by Obama’s nine-day trip to the Asia-Pacific when he marshaled momentum behind a new trans-Pacific trade pact, agreed on a new military partnership to base up to 2,500 Marines in Australia and announced that Hillary Rodham Clinton would become the first U.S. secretary of state in 50 years to visit Burma, also known as Myanmar.

Clinton made the trip last December, stating that the United States is prepared to “walk the path of reform” with the Burmese leadership. In June, the Obama administration formally lifted prohibitions on U.S. economic investment in Burma, opening the door for American companies, particularly in the energy sector.

Suu Kyi visited Washington in September to receive the Congressional Gold Medal and meet with Obama, and that same month, Sein attended the U.N. General Assembly in New York, where he praised Suu Kyi and heralded “amazing changes” in Burma.

U.S. foreign policy experts who have recently visited the country said they saw signs of a serious commitment to reform. In a paper for the Brookings Institution, Jeffrey Bader, who served as senior director for East Asian Affairs on the National Security Council from 2009 to 2011, said newspapers published “lively debates” and ordinary people “spoke of the profound change in atmosphere and of their willingness to speak out on matters where there was fear and silence only recently.”

Michael Green, senior vice president for Asia at the Center for Strategic and International Studies, also said he found a “serious intention” to reform the political system and get the military “out of the government.” But he cautioned that the movement is in a “very precarious state,” noting that the country’s generals are guaranteed 25 percent of the parliamentary seats and maintain control of the chairmanship.

“But everyone who’s in the cabinet, in the president’s office, and, of course, Aung San Suu Kyi, are working together and are determined to do this,” said Green, former senior director for Asian affairs at the NSC in the George W. Bush administration. “So there is enough of a kernel . . . of seriousness to make the president’s trip worthwhile.”

Human rights activists, however, said that whatever progress Burma has made has suffered significant setbacks in the past several months, as the ethnic violence between the Rakhine Buddhists and Rohingya Muslims has accelerated. Burma released 452 prisoners this week in a good faith move ahead of Obama’s visit, but none were political detainees.

Samantha Power, the NSC’s senior director for multilateral affairs and human rights, said the Burmese government has taken some steps to address the abuses, sending in national troops to areas where local forces have been violent.

But, she added, “There has to be a sustainable security solution so that people aren’t living in the kind of fear and, really, terror that they’re living with today.”