A pair of U.S. F-35 fighter jets are on display at an airshow in Singapore this week, vying for potential customers in a volatile region. But Washington won’t sell its most-advanced warplanes to just anyone.

Several key U.S. allies already have F-35s, including South Korea, Australia and Japan, and Singapore is set to follow suit. Next in line could be Thailand, America’s long-standing treaty ally in Asia. But analysts say there’s no guarantee that Washington will approve the sale, because of Thailand’s close defense ties with U.S. strategic rival China.

Two of the plane’s three variants, the F-35A and the F-35B, have been sent to the biennial Singapore Airshow, together with a number of other U.S. military aircraft. That’s widely seen as an effort to impress the regional market amid concerns about, in Washington’s words, China’s “coercion and aggression that is most acute in the Indo-Pacific.”

The stealth fighter jet, manufactured by U.S. defense aviation giant Lockheed Martin, has been in the news for the wrong reasons after an F-35C crashed on the USS Carl Vinson aircraft carrier in the South China Sea in late January. The U.S. military is in the process of retrieving the plane, which fell to the bottom of the ocean.

Despite that mishap, the F-35s are still “the most technologically advanced fighters on the market today,” said Richard Bitzinger, senior fellow of the Military Transformations Program at the S. Rajaratnam School of International Studies in Singapore.

Tim Cahill, Lockheed Martin’s senior vice president for global business, confirmed on the sidelines of the Singapore Airshow that Thailand had expressed interest in the F-35 fighter but it’s up to the U.S. government to clear it, Reuters reported.

Cahill was quoted as saying:  “This will be a U.S. government policy decision.”

Strong interest

The Thai government and air force could not be reached for comment.

In mid-January, the nation’s cabinet agreed in principle to back the Royal Thai Air Force’s plan to procure four new fighters for 13.8 billion baht (US$415 million) in the 2023 fiscal year to replace the air force’s aging fleet of F-16A/B Fighting Falcons.

The air force chief, ACM Napadej Dhupatemiya, had previously expressed a strong interest in F-35 stealth fighter jets and seemed confident about the purchase since the aircraft had become more affordable at US$80 million per shot. He said the F-35 had “top notch” performance and the purchase would enable Thailand “to stay in the same league of countries with advanced fighters.”

Andreas Rupprecht, an expert on China’s military aviation, said the interest in the U.S. fighter jet was surprising “as Thailand has been shifting more towards China in recent years.”

“I would have thought [the Thai air force] would opt for something like the Chinese-made J-10C, especially after the Chinese fighters took part in recent Sino-Thai Air Force joint training exercises,” Rupprecht said.

J-10C is China Air Force’s multirole fighter, 25 of which are being sold to Pakistan.

The supposed purchase of U.S. fighter jets has also met with criticism in Thailand, with some analysts saying it is “more about ulterior motives rather than strategic objectives.”

“Thai air force interest in F-35s is opportunistic because a military-backed government is in office and the military has been entrenched in power after two coups in 2006 and 2014,” said Thitinan Pongsudhirak, a leading political scientist and professor at the famed Chulalongkorn University.

“Unlike Japan, South Korea or Taiwan, Thailand’s threat perceptions do not call for the acquisition of advanced F-35s,” Thitinan said.

“Thailand has close relations with China, and no border issues with its next-door neighbors.”

Lack of trust?

Thailand’s growing military ties with China are one of the main reasons why the U.S. would be reluctant to sell their state of the art aircraft to Bangkok, said Ian Storey, senior fellow at the ISEAS-Yusof Ishak Institute in Singapore.

“Thailand is a U.S. treaty ally, so it has a strong case,” argued Storey.

“But the Americans would still be concerned that the jet fighter’s sensitive technologies might be compromised by the Thai military to its Chinese counterpart,” he said.

“The U.S. kicked Turkey out of the F-35 program because it got too cozy with Russia,” said Bitzinger, who linked the termination of the sale of 100 F-35As to Ankara in 2019 to Turkey’s decision to purchase S-400 air defense systems from Russia.

A statement by the White House at the time said: “The F-35 cannot coexist with a Russian intelligence collection platform that will be used to learn about its advanced capabilities.”

Bitzinger drew a comparison with Thailand’s hopes to acquire the F-35.

“Thailand already buys a lot of Chinese weaponry: frigates, submarines, and tanks are just a few of the latest items that it’s bought from China,” he said.

“Given even greater concerns over protecting F-35 technologies, I doubt if Washington would be more willing to trust Thailand,” he added.

Besides the F-16s and F-5s, the Thai Royal Air Force currently operates 11 Swedish JAS-39 Gripen fighters and aviation experts say Thailand could buy more of those, or the French Rafale, like Indonesia.

Last week, Jakarta signed an acquisition contract for 42 Dassault Rafale multirole combat aircraft, the first batch of six to be delivered by 2026.

Just a few days ago, the Biden administration also approved a nearly US$14 billion arms sale of up to 36 F-15 fighter jets to Indonesia, and that could be an option for Thailand, according to Storey.

F-35’s growing market

The F-35 Lightning II is single-seat, single-engine, multirole combat aircraft with stealth capabilities to evade radar. Of the three variants of the F-35, the F-35A is the least expensive; the F-35B can perform short take-off and landings; and the F-35C – the type involved in the Jan. 24 crash – is designed to operate from aircraft carriers.

Some of Washington’s most trusted allies and partners in the Indo-Pacific have already purchased, or are in the process of purchasing the F-35.

Australia acquired 72 F-35As and received the first 44 by late 2021. The Australian Royal Air Force expects to have all its F-35 aircraft operational by the end of 2023, and is considering to buy more.

Japan, facing threats from China, in December 2018 announced plan to acquire 105 F-35 aircraft including 63 F-35As and 42 F-35Bs, on top of 42 F-35As it acquired earlier.

South Korea bought 40 F-35As in 2014 and approved a follow-on batch of 20 more. Seoul is also considering to purchase the F-35B variant.

Singapore became the latest country in the Indo-Pacific to procure the stealth fighters from the U.S. with the first batch believed to be 12 F-35Bs. The U.S. State Department approved Singapore’s request in January 2020 and the aircraft are due for delivery in 2026, according to the aviation industry monthly Aviation International News.