SINGAPORE — Sen. Chris Coons’ trip to Singapore last week began with two notable stops.

The first was Taiwan. Shortly before Coons arrived, China launched a military drill near the island nation, which the head of U.S. Indo-Pacific Command called a “rehearsal” of an invasion.

The second was to the Philippines, whose vessels face harassment from the Chinese Coast Guard on a regular basis in areas around the South China Sea that both countries claim as their own territory.

These issues were major topics of discussion at Coons’ last stop — the Shangri-La Dialogue, Asia’s largest defense conference.

The first night of the summit, Philippine President Ferdinand Marcos Jr. said that if China’s military activities killed a Filipino citizen, his government would likely consider it an act of war, which could draw the U.S. into the conflict given it is allied with the archipelago nation.

Two days later, Chinese Defense Minister Adm. Dong Jun spent much of his remarks decrying perceived “separatism” from Taiwan, an island nation that China considers a rogue province and has threated to take back by force. Dong warned that the odds of “peaceful reunification” with the island were “eroding.”

The rhetoric at the Shangri-La Dialogue raised an important question about security in the Indo-Pacific region: Taiwan’s independence and disputed territory in the South China Sea have long been tense subjects, but which is more likely to lead to a conflict?

That’s a major part of Coons’ job. The Democrat from Delaware sits on the Senate Committee on Foreign Relations, which will help steer $2 billion in new long-term military aid to the region.

The U.S. is already mapping out where that money will go, along with an additional $1.9 billion in short-term funding. Most of it will head to Taiwan, but how the government divides the entire amount will in part depend on where the threat seems most acute.

“There are a whole series of conversations underway between the United States and Taiwan, the United States and the Philippines, and a half dozen other regional actors,” Coons said in an interview. “Those conversations should then inform the final downselect in terms of how much for each and for what purpose.”

“The larger issue,” he added, “is to not let this take too long.”

Two threats

But how long is too long? Some in Washington have grown increasingly concerned about the chances of a short-term conflict over Taiwan, due in part to China’s large military buildup under its leader, Xi Jinping.

Equipment updates are part of China’s military modernization effort, but training also contributes to that. Its drills around Taiwan have become more aggressive in recent years, and it now regularly breaks the unspoken but once sacrosanct rule to not cross the median line of the Taiwan Strait. Some in Congress and the Pentagon worry the new status quo could make China’s real threat harder to assess.

Contrast that with the Second Thomas Shoal, a disputed reef in the South China Sea. Beijing claims sovereignty over the area, despite a 2016 ruling from the United Nations Convention on the Law of the Sea, which invalidated that approach.

Since last year, China has used Coast Guard ships and other vessels to fire water cannons at and ram Philippine ships, among other means of harassment. Some Philippine ships were damaged under the stress.

Observers wonder where the Philippines will draw a red line and invoke a mutual defense treaty that the U.S. says it is prepared to fulfill. Marcos didn’t say the death of a Filipino citizen would automatically trigger that deal, but he did say it would be “very close to what we define as an act of war.”

“A lot of folks agree that Taiwan remains the most important challenge because the escalation potential is so high,” said Greg Poling, an expert on Asian security at the Washington-based Center for Strategic and International Studies think tank. “But the South China Sea can’t be ignored because it’s got the highest likelihood of escalation, even if it’s relatively low.”

In response to the different threats, both Taiwan and the Philippines have been upgrading their respective militaries. Many of Taiwan’s goals involve the purchase of American-made weapons through the Pentagons’ Foreign Military Sales program, although a large share of these are taking longer than either party wants.

Rep. Michael McCaul, R-Texas, said there were a total of 22 weapons systems he approved “going back to four years ago” in his position as chair of the House Foreign Affairs Committee. But those arms “have yet to go out of the country,” he noted during an interview at the Shangri-La Dialogue.

Meanwhile, the Philippines has modified its military modernization plan amid clashes with Chinese forces, and it also signed a deeper security deal with the U.S. last year. That cooperation has led to larger military exercises between the two countries, including one that finished a few weeks before the conference.

‘Two hot wars’

To further harden each country’s defenses, the U.S. passed a $95 billion security bill in April. It included about $4 billion in foreign military financing for longer-term arms sales and another $1.9 billion to replace stocks the U.S. sends from its own inventories.

Coons said he discussed this aid in his meetings with Taiwanese and Filipino officials, including the presidents of both countries.

The question of how to spend that money depends on several variables. Aside from the sense of urgency related to each threat, Coons said, the U.S. will assess how much equipment each military can absorb in any given point of time.

That will be harder to answer for the Philippines, which, unlike Taiwan, has received small amounts of American-made materiel in recent years, relatively speaking.

“Last year the number was $40 million” of financing, Coons said, chuckling as he added: “Somewhere between $40 [million] and $500 million is probably the right number.”

Another factor is how fast American defense companies can deliver — a topic McCaul raised multiple times, given the U.S. is also supplying two other partners. Arming Israel and Ukraine — the former is fighting a war against the militant group Hamas, and the latter is defending itself against a Russian invasion — has put a strain on the defense industry.

“We’ve got two hot wars, and we’re in a hot zone right here,” he said.

In addition, while both McCaul and Coons agreed most of the funding will go toward Taiwan, and to a lesser extent the Philippines, there are other countries in the region with needs. The U.S. now has money to help them, but it’s a limited amount.

“My view is that we should principally focus on Taiwan and the Philippines right now,” Coons said. “But look, even $20 [million] or $40 million in [foreign military financing] for some of our partners out here would be significant.”

Noah Robertson is the Pentagon reporter at Defense News. He previously covered national security for the Christian Science Monitor. He holds a bachelor’s degree in English and government from the College of William & Mary in his hometown of Williamsburg, Virginia.

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