Amid rising regional tensions, more than 17,000 Philippine and U.S. soldiers began their largest-ever joint military drills on Tuesday, April 11, which will last for two weeks.

This follows on the heels of China’s three days of military exercises around Taiwan, following Taiwanese President Tsai Ing-wen meeting with U.S. House of Representatives Speaker Kevin McCarthy in Los Angeles.

The South China Sea is fraught with territorial disputes which involve conflicting island and maritime claims in the region by several sovereign states, namely, Brunei, the People’s Republic of China (PRC), Taiwan, Indonesia, Malaysia, Philippines, and Vietnam.

Prior to these exercises, plans had already been announced to expand the Enhanced Defense Cooperation Arrangement (EDCA) with the United States of America to add four new bases to the existing five. Three of these bases will be located to the north of Luzon Island, where the Philippines makes its closest approach to Taiwan.

These developments have caused concerns—from China, who see these moves as the US strengthening its forces to support its allies, Taiwan and the Philippines and beefing up its military might in the region; from local residents, who are afraid of a possible offensive attack from China as a result of increased US presence in their province; and from students, activists, and peace advocates who oppose foreign military presence in the country.

China’s Foreign Ministry spokeswoman Mao Ning said at a regular news briefing that increased US military forces “would only lead to more tensions and less peace and stability in the region.” Her Foreign Ministry colleague Wang Wenbin said that the US drills “must not interfere in South China Sea disputes, still less harm China’s territorial sovereignty, maritime rights and interests and security interests.”

In response to the new bases under the EDCA, the governors were split on the use of their provinces as hosts. The Governor of Cagayan, the province closest to Taiwan, personally opposes and disagrees saying, “For me, it is inimical to the interest of our provinces and the Cagayanons,” he told ABS-CBN News. But he admitted that it was the president’s call, ultimately.

The League of Filipino Students and other student groups staged a protest rally against the military exercises in front of the US embassy in Manila, but the protest was broken up by the authorities, and a number of participants arrested.

What is the Balikatan? And why do the US and the Philippines hold these joint military drills yearly?

Balikatan, Tagalog for ‘shoulder-to-shoulder,’ is a longstanding bilateral exercise between the Philippines and the United States highlighting the partnership between both countries, rooted in a mutual defense treaty between the Republic of the Philippines and the USA, signed in Washington in 1951.

This treaty aims to “declare publicly and formally their sense of unity and their common determination to defend themselves against external armed attack so that no potential aggressor could be under the illusion that either of them stands alone in the Pacific area.”

This year’s exercises are the 38th and include 111 members of the Australian Defense Force. Military assets that will be used for the exercises come from the arsenals of both the armed forces of the Philippines and the United States. Other allied countries have been invited as observers to the war games, including Japan, the United Kingdom, Canada, India, France, and some ASEAN nations.

For the first time, the Philippines and the United States will hold live-fire drills at sea. Simulated war games will be held in North and Central Luzon, Palawan, as well as in Antique. Among this year’s main events is the holding of a cyber defense exercise, which will be held just as both the Philippines and US military forces continue to modernize their capabilities.

Can increased US presence and access to Philippine bases provide launch pads for combat operations if armed clashes over flashpoints like Taiwan or the South China Sea arise?

As reported in US magazine the Nation, International Peace Bureau co-president Corazon Valdez Fabros expressed concern that increased US military presence in the region would make war between the US and China more likely.

“Imagine you have a visitor who comes into your house,” Fabros said. “You welcome this visitor. But this is a visitor who has all the guns, all the materials that basically you cannot object to because they are fully loaded. And you cannot even tell this visitor to get out of your house when you want them to get out.”

“That is the US,” she said.

“This may not be something that for sure is going to happen. But the mere fact that the US is here makes it more likely something can happen. Maybe there’s a miscalculation. These things happen.”

In response, Philippine President Ferdinand Marcos Jr reiterated that the US would not be able to access military sites for offensive moves. Our mutual treaty is purely defensive in nature. “The Philippines will not allow our bases to be used for any offensive actions. This is only meant to help the Philippines should the need arise,” he said.

Some experts also say that the decision over any military operations in defense of the Philippines will not rest only on the President’s decision. It would require the approval of the Congress who, as representatives of the people, should reflect the Filipino people’s will and the country’s best interests.

Is continuing to conduct these annual military drills and expanding military bases in the Philippines in the best interest of the country?

Not according to ex-president Duterte. He said, “Because of these EDCA bases, we will be the multiple targets of Chinese missiles once war breaks out between China and the US. Is that in our national interest?”

While American and Philippine officials say the drills are designed to build up defense capabilities, not signal aggression, activists from Filipino advocacy and war groups in the US disagree and gathered in Times Square to protest.

“We are here…to condemn the expansionist endeavors of the United States military,” said Kaloy Ceballos of Anakbayan Manhattan, local chapter of the pro-democracy Filipino youth movement.

“There is no doubt that this is America’s buildup to war in the Asia Pacific,” said Nina Macapinlac, secretary general of Bayan USA, the American chapter of the Filipino organization that advocates for democracy free from foreign influence. The Philippines should strengthen its national sovereignty, rather than align with either Beijing or Washington, demonstrators said.

But, for as long as the Mutual Defense Treaty and other treaties like the EDCA are in force, military endeavors and increased US presence in the country like the Balikatan will continue, and regional tensions will continue to spark and cast a pall over the country and the Asian region.