Carolyn Kaster / AP

When President Obama stood beside Tran Dai Quang, the Vietnamese leader, on Monday and announced the end of America’s arms embargo on Vietnam, he did so despite pleas from human-rights groups to delay a decision until the Communist regime released political prisoners.

Obama portrayed the decision as one based on removing one of the last vestiges of the war, which ended in 1975 with the fall of Saigon. The U.S. would wait two more decades to restore diplomatic relations with its Cold War-era adversary, and it wasn’t until 2000 that an American president, Bill Clinton, visited Vietnam. Six years after that, President George W. Bush followed suit. And while the U.S. has engaged in trade with Vietnam, and has become, in fact, one of the country’s largest trading partners, it maintained the embargo for years, saying its removal depended on improvements in Vietnam’s human-rights record. In recent years, the country has imprisoned more than 100 political dissidents and has cracked down on dissenting speech online—though Human Rights Watch notes an “increasing numbers of bloggers and activists have called publicly for democracy and greater freedoms.”

Obama acknowledged the two countries “still have differences” on human rights. Indeed, as The New York Times reported Tuesday, some of those differences were grounded in the fact that while Obama met with six activists in Hanoi, several others who were scheduled to meet with him were prevented by Vietnamese authorities from doing so. Human Rights Watch, which regards Vietnam’s human-rights record as “dire in all areas,” identified them as Pham Doan Trang, Nguyen Quang, and Ha Huy Son. The organization has been especially critical of Obama’s visit, as is clear in this tweet by its executive director.

But human-rights concerns notwithstanding, Obama’s decision on the arms embargo may have to do as much with Vietnam’s strategic importance as its capacity to buy weapons, and the president’s famous pivot toward Asia.

“[T]he increasingly tense situation in the South China Sea, and Vietnam’s growing strategic and economic importance, outweigh U.S. concerns about Hanoi’s admittedly terrible human rights record,” writes Joshua Kurlantzick, a senior fellow for Southeast Asia at the Council on Foreign Relations. He adds: “The lifting of the embargo, and Vietnam’s increasing willingness to be seen, regionally, as a close partner of the United States, is a sign that Hanoi is abandoning its decades-old strategy of balancing relations between Beijing and Washington.”

Indeed, Vietnam and China have had a history of tensions and conflict. Both claim the Spratlys and Paracel island chains. China’s recent military activity in the South China Sea, where it has built artificial islands, has many of its neighbors worried; but Vietnam is especially so because those islands are only about 300 miles from the Vietnamese coast.

The U.S. has expressed concern over China’s actions in the South China Sea, and Monday’s announcement on the arms embargo may be tied to that concern. The fact that Vietnam is the world’s fifth-largest arms buyer probably didn’t hurt either. The Stockholm International Peace Research Institute notes that Vietnam’s arms imports rose almost 700 percent from 2011 to 2015. The country buys most of its weapons from Russia, but has been considering diversifying its supply base, and has already bought some military equipment from Israel. Still, experts note that the lifting of the embargo is unlikely to benefit U.S. arms manufacturers, mainly because U.S. weapons, while more sophisticated, are also more expensive. And even when, in 2014, the U.S. eased the embargo to allow Vietnam to buy non-lethal maritime equipment, the country did not turn to American weapons suppliers.

Obama’s own view of Asia may also have informed his decision. As my colleague Jeffrey Goldberg wrote in April, Obama believes “America’s economic future lies in Asia.”

“From his earliest days in office, Obama has been focused on rebuilding the sometimes-threadbare ties between the U.S. and its Asian treaty partners, and he is perpetually on the hunt for opportunities to draw other Asian nations into the U.S. orbit,” Goldberg wrote. “His dramatic opening to Burma was one such opportunity; Vietnam and the entire constellation of Southeast Asian countries fearful of Chinese domination presented others.”

Trade is one part of that equation: Obama has engaged Vietnamese officials on the Trans-Pacific Partnership, a key policy goal of the president. Vietnam agreed to recognize independent labor unions in the country as part of the massive agreement that involves 12 countries, including the U.S. and Vietnam. But, as Goldberg pointed out, U.S. strategic interests are another part:

Administration officials have repeatedly hinted to me that Vietnam may one day soon host a permanent U.S. military presence, to check the ambitions of the country it now fears most, China. The U.S. Navy’s return to Cam Ranh Bay would count as one of the more improbable developments in recent American history.

Still, Obama, in his remarks to reporters on Tuesday while meeting with some of the Vietnamese activists, did note that while the U.S. and Vietnam agreed on several things, disagreements remained.

“Vietnam has made remarkable strides, the economy is growing quickly, the Internet is booming, and there’s a growing confidence here,” he said. “But as I indicated yesterday, there’s still areas of significant concerns in terms of areas of free speech, freedom of assembly, accountability with respect to government.”

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