The Philippines and United States need to revisit their longtime mutual defense pact to address Beijing’s increasing use of so-called gray-zone activities – or acts of aggression short of an armed attack – in the disputed South China Sea, experts said.
Under the 1951 Mutual Defense Treaty (MDT), the two allies are compelled to come to each other's defense in the event of "an armed external attack," but the term is ambiguous and needs to be more clearly defined, according to analysts interviewed by BenarNews, an RFA-affiliated news outlet.
Article V of the treaty “needs to be more clearly discussed and interpreted” by both countries, said Don McLain Gill, a geopolitical analyst based in Manila.
The article states that the MDT covers “an armed attack on the metropolitan territory of either of the parties, or on the island territories under its jurisdiction in the Pacific Ocean, its armed forces, public vessels or aircraft in the Pacific.”
In recent years, China has intensified its harassment and intimidation of Philippine government ships and other vessels in the West Philippine Sea, Manila’s name for waters of the South China Sea that lie within its exclusive economic zone (EEZ).
“There needs to be a firmer operational definition of an ‘armed attack,’ because without doing so, China will continue to exploit such terminological ambiguities,” Gill told BenarNews.
“It’s still an ambiguous term. Should firearms be used to trigger the MDT? If so, it does not address the casualties on our side.”
He was responding to questions about a March 5 incident where four Philippine Navy sailors sustained minor injuries while aboard a military-contracted civilian vessel, when blasts from Chinese water cannons shattered their boat’s windshield.
The dramatic moment, which was caught on video, occurred as China Coast Guard (CCG) ships tried to block the Philippine boat, the Unaizah May 4, from carrying out a resupply mission to Ayungin Shoal (Second Thomas Shoal).
“The focus must also be on the potential harm to human life China’s unfriendly acts may cause,” Gill said.
The incident last week marked the first time that injuries were reported in any of the tense incidents at sea that have become more frequent lately, as Chinese ships try to block Philippine ships and boats from delivering supplies to the BRP Sierra Madre, a rusty World War II-era ship that serves as Manila’s outpost in Ayungin Shoal.
While such close encounters at sea between Philippine and Chinese coast guard ships increased in 2023, U.S. Secretary of Defense Lloyd Austin cited the MDT in warning that Washington would help defend Manila in case of an armed attack "anywhere in the South China Sea," including on Philippine Coast Guard (PCG) vessels.
In the immediate aftermath of the March 5 incident, Philippine President Ferdinand Marcos Jr. dismissed calls that Manila move to have the treaty invoked over it.
While “his administration viewed the incident and such “dangerous maneuvers” by China with “great alarm,” there was no need at this time to take that step on the MDT, he said.
Five months after he took office in 2022, as he talked about the possibility of a stronger U.S. military presence in the Philippines, Marcos said that the mutual defense treaty with the United States was “continuously under negotiations and under evolution.”
In 2023, as tensions also simmered between China and the U.S. over Taiwan, the Marcos administration agreed to give American forces greater access to military bases in his country. Late last year, the U.S. and the Philippines also launched joint patrols around the archipelago.
Sherwin Ona, a political science professor at De La Salle University in Manila, said he agreed with Marcos and noted that the boat that came under attack was a civilian vessel.
In his view, Beijing is aware of the language in the treaty that does not clearly define a red line, and is exploiting that by carrying out gray-zone tactics in the contested waterway.
“The framing of conflict is so far within the gray-zone approach of the People’s Republic of China. I think Beijing is conscious of this and will avoid a full-scale naval confrontation with the Philippines and the U.S.,” Ona told BenarNews.
Wider definition of ‘armed attack’
Analyst Gill, however, said that if the definition of armed attack is merely limited to military confrontation, this allows China to carry on with its aggressive actions at sea.
“If armed attack will only mean a direct military confrontation, then that opens up more pathways for China to inflict harm on Filipinos at sea,” Gill said.
“Given last week’s incident, one may ask that if China’s belligerent activities in the Philippines’ EEZ may eventually critically injure or kill members of the Philippine crew, should Article V be implemented?” he said.
Antonio Carpio, a South China Sea analyst and a former Supreme Court justice, said the Philippines could approach the U.S. to talk about a possible expansion of definitions of wording in the treaty.
“‘Armed attack’ means use of lethal weapons like cannon, missiles or guns. We can discuss with the U.S. to define ‘armed attack’ to include use of laser beams that are permanently blind since such use is already outlawed by an international convention,” Carpio said in a message to BenarNews.
Last year, a CCG vessel pointed a military-grade laser at a Philippine Coast Guard ship, temporarily blinding the Filipino crew.
‘Option of last resort’
But Rommel Ong, a retired Philippine Navy rear admiral, believes the two countries will not include such acts of aggression in the MDT.
“I don’t think that’s going to happen. The Philippines and the U.S. are both trying to avoid invoking the MDT for minor incidents,” Ong told BenarNews.
“That’s the option of last resort. The actions of China are still within the bounds of non-kinetic. It’s just that we’re not used to conflicts at sea,” he said.
He mentioned the cod wars between the United Kingdom and Iceland during the 1950s to 1970s over rights to fish in Icelandic waters. Both European countries engaged in gray-zone tactics by ramming and blocking each other’s ships.
“MDT is like a nuclear bomb. Its effectiveness is in its deterrent value. But once you use it, it loses its value.”
With these limitations, the Philippines appears to have no option but to resort to joint patrols with the U.S. and other like-minded allies, analyst Ona said.
He added that the Philippines must fast-track military and coast guard modernization programs and continue its transparency program, whereby they publicize cases of Chinese intimidation and incursions in the West Philippine Sea.
Marcos has repeatedly called on foreign nations to support the landmark international arbitration ruling in 2016 that sided with Manila and invalidated Beijing’s sweeping claims in the South China Sea.
During an official visit to Germany this week, Marcos noted that 60% of world trade passed through the vital waterway.
“It’s not solely the interest of the Philippines, or of ASEAN, or of the Indo-Pacific region but the entire world. That is why it’s in all our interest to keep it as a safe passage for all international commerce that goes on in the South China Sea,” Marcos said during a joint press conference on Tuesday with German Chancellor Olaf Scholz.
Marcos has relied on international allies and partners, striking deals on defense cooperation even with non-traditional allies to counter Chinese aggression. Aside from the U.S. and Germany, Japan, Australia, France, the United Kingdom, and India have expressed support for Manila over the South China Sea dispute.
Jeoffrey Maitem in Cotabato City, southern Philippines, contributed to this report.
BenarNews is an RFA-affiliated news outlet.