BANGKOK, Thailand — Think America is skittish over China’s rising power? Consider the view from Southeast Asia, witness to centuries of Chinese intervention, weapons trafficking and, in Vietnam, outright invasion.

Though China’s navy has by some estimates outgrown America’s, its military sway over Southeast Asia remains weak. Its weapons sales in the region, a marker of influence, are relatively meager. Its joint military drills with local allies — only two this year — are sporadic and small.

Chinese marines arrived in Thailand this week to join a joint military drill with Thai troops, marking the first time Chinese marines went abroad to conduct joint exercises with foreign forces. Meanwhile, the U.S. military holds about 300 annual exercises in the Pacific region, including the world’s largest war games in Thailand.

Though buoyed by China’s rising economy, Southeast Asia is rebuffing China’s attempts to pull the region under its defense umbrella. “They just can’t ramp it up, mostly because of Southeast Asian resistance,” said Ian Storey, who analyzes China’s military at the Singapore-based Institute for Southeast Asian Studies. “That sort of relationship with China still makes this region very anxious.”

As Hillary Clinton tours the region to shore up American support, here’s a look at U.S. courtship — and Chinese counter-courtship — in four strategically crucial Southeast Asian countries.

THAILAND: Perhaps America’s truest Asian military ally, Thailand plays host to the world’s largest multinational war games: “Cobra Gold.” Each year, more than 11,500 troops from the U.S., Thailand, South Korea, Indonesia and Singapore stage beach assaults, rescue missions and more. The Chinese are invited too — but only to watch.

In recent years, China has pursued its own war games with Thailand. The People’s Liberation Army even suggested all-expenses-paid “Cobra Gold”-style exercises in 2010. Instead, Thailand has accepted only small-scale games like “Blue Assault,” 20 days of Marine Corps drills now ongoing along Thailand’s coast.

China has repeatedly appealed to Thailand’s generals, namely after a 2006 military coup that temporarily cut off U.S. funding. (China offered $49 million in military credits that year, more than twice the amount offered by the U.S.) But while their relationship is growing, Thailand still keeps the Chinese at arm’s length. Full-on war games risk angering the U.S., fearful the Chinese will learn American invasion tactics from U.S.-trained Thai troops.

MYANMAR: Myanmar is the only Southeast Asian country securely under China’s military sway. U.S. defense companies are strictly forbidden from exporting arms to Myanmar, run by a military that has tortured and killed ethnic tribes for more than 60 years. Myanmar has instead turned to China for more than $164 million worth of weapons and equipment in the last 10 years, according to the Stockholm International Peace Research Institute.

This investment, accounting for 63 percent of China’s total arms sales to Southeast Asia from 2000-2008, has transformed Myanmar’s army from a ragtag counter-insurgency outfit into a capable fighting force.

What the U.S. fears most, however, is Myanmar’s nuclear ambitions. A Myanmar army defector, Maj. Sai Thein Win, has supplied ample evidence to prove the isolated backwater has a nuclear weapons program, said Robert Kelley, former director of the International Atomic Energy Agency. Still, the program is rudimentary, he said. “The workmanship is extremely poor,” he said this week in Bangkok. “I can buy many of these components from the hardware store ... and I think I can build them just as well.”

China has said little about Myanmar’s nuclear ambitions. Clinton, however, is expected to reiterate this week her fears that Myanmar’s nuclear program remains a threat — particularly if it’s aided by North Korea.

VIETNAM: Jaded by invasions and proxy wars, Vietnam’s defense policy is distilled into three ultimatums: No military alliances, no foreign bases and no relying on a third-party country to attack its enemies. In August, a Vietnamese deputy defense attache in Beijing, Chu Ngoc Nho, told the China Daily that “We are not going to be military allies with the U.S. or any other country.”

But Vietnamese anxiety over China’s rise — shared by the U.S. — is encouraging an intimacy that would have been unthinkable decades ago. They’re conducting small naval exercises in the South China Sea, where Vietnam and China are tangled in territorial disputes. U.S. warships have also docked to welcome aboard senior Vietnamese generals. A lifted ban on all but “lethal-end” arms has even helped Vietnam repair old weapons seized after the U.S. retreat in 1975.

But perhaps the strongest affront to China is America’s proposal to share nuclear technology with Vietnam, ostensibly to power its booming industries. U.S. officials are openly considering an agreement that would allow Vietnam to enrich its own uranium, a stepping stone towards assembling nuclear weapons.

Vietnam’s potential to produce a nuclear bomb — or even a nuclear-powered submarine — has been overstated, Storey said. “In fact, it’s almost unthinkable,” he said. The Vietnamese will also be mindful not to grow too close to its former enemy. “They’ve got to play a very careful game with China,” Storey said. “They can’t seem to be antagonizing them, because the Chinese can make life very difficult for them.”

Read more on Clinton in Vietnam. As Hillary Clinton arrives in Hanoi, will human rights trump China?

INDONESIA: According to the U.S. Defense Department, up to 80 percent of China’s fuel imports pass through the so-called naval “choke points” around Indonesia. But despite China’s huge need for stability along this island chain, they have largely failed to influence the Indonesian forces tasked with securing it.

More than most Southeast Asian countries, Indonesia has sought China’s military help, namely in acquiring the technology to mass produce its own weapons and equipment.

But Chinese reluctance to share its secrets, Storey said, has frayed the relationship.

Previously, while under U.S. arms embargoes for human rights abuses, Indonesia was heavily courted by China’s defense industry. But after buying $11 million worth of anti-ship missiles in 2005, the Indonesians have shown little interest in buying more Chinese advanced weaponry, known to be less reliable than Russian, European and U.S. weapons.

“The Chinese attempted to drive a wedge between Indonesia and the U.S.,” Storey said. “But this relationship was repaired fairly quickly.”

Since 2006, the U.S. has poured $47 million into Indonesia’s anti-piracy and other military programs, including a network of radars through its precarious shipping lanes. Amidst criticism this year, the U.S. lifted a ban on aiding Kopassus, Indonesia’s elite commando unit accused of torture and other human rights abuses.

“Human rights are important domestically [in the U.S.], but considering China, they have to beef up their Southeast Asia presence,” Storey said. “With the Indonesian military reforming itself, and the fact that they’re a democracy, the U.S. has to hope these abuses won’t happen again.”

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