The death of Thailand's King Bhumibol Adulyadej on Thursday adds a new layer of uncertainty to U.S. President Barack Obama's faltering "pivot" to Asia less than a month before the Nov. 8 U.S. presidential elections.

 

The king was a key figure in cementing the long-standing alliance between the United States and Thailand after World War Two, in a reign that spanned the turmoil of the Vietnam War and development of the Association of Southeast Asian Nations (ASEAN), which Washington still considers vital to maintaining its influence in the region.

 

King Bhumibol's death comes at a time when momentum had already begun to falter in Obama's signature policy of rebalancing the U.S. diplomatic and security focus to the Asia-Pacific region in the face of China's rapid rise.

 

The main economic pillar of the rebalance, the 12-nation Trans-Pacific Partnership trade deal, is languishing in the U.S. Congress with no guarantee that Obama will be able to push it through before leaving the presidency to Hillary Clinton or Donald Trump, both of whom say they oppose the deal.

 

Clinton was a key architect of the rebalance as secretary of state under Obama, but Trump in campaign statements has called into question the extent to which he would maintain the U.S. security commitment to East Asia.

 

Obama's efforts to boost security ties with Southeast Asia have come in response to China's pursuit of territorial claims in the South China Sea, a vital strategic waterway.

 

However, a torrent of anti-American rhetoric from new Philippines President Rodrigo Duterte has raised questions about the future of the key U.S. military relationship with Manila just months after Washington reached an agreement to allow it rotating access to bases in the country.

 

Other Southeast Asian countries, such as Indonesia and Malaysia, are focused on internal political issues and are avoiding playing any leadership role in ASEAN, while even traditionally reliable regional ally Australia is treading carefully, anxious to avoid jeopardizing its economic relations with Beijing.

 

Thailand already was occupying a back seat in regional affairs following a 2014 military coup seen as a means to maintain stability during the king's long illness, and is expected to turn further inward during a prolonged mourning period and potentially politically fragile royal succession.

 

King Bhumibol's son, Crown Prince Maha Vajiralongkorn, who is expected to become Thailand's new king, lacks the strong connection to the United States of his father, who was born in Cambridge, Massachusetts.

 

MUCH HAS CHANGED

 

Murray Hiebert, a Southeast Asia expert at Washington's Center for Strategic and International Studies think tank, said much has changed since Obama announced his pivot policy in Canberra in 2011.

 

"The king's death adds to uncertainty in Southeast Asia, a region in considerable flux already. This makes the U.S. rebalance to Asia more difficult because the situation in so many countries is that of wait and see.

 

"When the pivot started, you had Thailand engaged, a new leader in Malaysia who wanted to engage, you had Aquino coming in the Philippines and very forward-leaning internationally and very open to the U.S.; you had an internationalist president in Indonesia. It was a rather different dynamic then."

 

U.S. leaders will go out of their way to stress Washington's high regard for King Bhumibol, who was revered in Thailand. On Thursday, Obama offered condolences to the Thai people and the King's family, calling King Bhumibol "a tireless champion of his country's development."

 

While Washington condemned the Thai coup, it has maintained security ties with Bangkok, particularly through annual military exercises called Cobra Gold.

 

"The fact that we have been able to remain closely tethered and stayed largely on track with Cobra Gold and other cooperative efforts, notwithstanding the military takeover ... is testament to the strong roots we have put down and the work that we're doing," the senior U.S. diplomat for Asia, Assistant Secretary of State Daniel Russel, said on Wednesday.

 

Even so, King Bhumibol's death means Washington finds itself having to rely more on Vietnam, its former foe, for any kind of strategic ballast in South Asia.

 

"The Vietnamese are providing the dynamism when it comes to strategic thinking," U.S. Ambassador to Vietnam Ted Osius told a Washington think tank on Tuesday.

 

"Indonesia is very internally focused right now ... Thailand is very internally focused, and Malaysia has a rolling political crisis," he continued.

 

"I don't know exactly what direction the Philippines is headed; Singapore has a lot strategic thinkers but it's a city state; I don't think you can really count on Laos, Cambodia and Myanmar to provide the strategic engine for ASEAN."

 

However, there appears little prospect for now that Vietnam would be willing to open its doors further to the U.S. military should the deal with the Philippines run into problems, given past animosities and concerns about China.

 

"I do not expect the Vietnamese calculation to be, 'Oh, the Philippines is doing whatever it's doing, let's race full steam ahead with the United States.' No, that's not about to happen," Osius said.

 

"The Vietnamese have been very measured in the pace at which they have expanded the security relationship."

 

Hiebert said Asian countries remain keen to see the U.S. pivot maintained, given their worries about China, but the pace was likely to flag further, presenting a tougher task to revive the initiative once Obama leaves power.

 

"I wouldn't declare the pivot dead ... I think there's still quite a bit of interest in the U.S., but some of the sort of dynamism that we saw earlier about building the region is a little bit diminished right now," he said.