Feb 6, 2023 - a Chinese Coast Guard (CCG) 

vessel illuminated the bridge of a Philippine 

Coast Guard vessel (BRP Malapascua) with a 

military-grade laser, temporarily blinding 

some of the crew. BRP Malapascua was resupplying Marines aboard BRP Sierra 

Madre, a Philippine naval vessel grounded 

in international waters since 1999 at Second 

Thomas Shoal (2TS) within the Philippine 

exclusive economic zone (EEZ). The Philippines filed a diplomatic protest against the 

PRC, calling the CCG vessel’s actions a 

“blatant disregard for, and a clear violation 

of, Philippine sovereign rights.”

The actions by the CCG vessel on Feb 6 

reflect a pattern of provocative and unsafe 

conduct by the PRC against the Philippines 

in relation to BRP Sierra Madre and 2TS. In 

recent years, PRC vessels and aircraft have 

used various measures to interfere with 

Philippine efforts to resupply BRP Sierra 

Madre, from dangerous maneuvers at sea to 

water cannons at close range. At issue is the 

PRC’s claim to territorial sovereignty over 

2TS – a claim that was roundly debunked in 

a legally binding decision by a United 

Nations Arbitral Tribunal in 2016. 

2TS, also known as Ayungin Shoal , is a low

-tide elevation (LTE) in the Spratly Islands, 

approximately 104 NM from the Philippine 

Island of Palawan’s archipelagic baselines. 

As an LTE situated wholly outside any 

nation’s territorial sea (TTS), 2TS does not 

generate a TTS of its own and is not 

subject to any claim to sovereignty or 

appropriation by any State under 

international law. Unlike the PRC, the 

Philippines does not make an unlawful 

claim to sovereignty over 2TS.

Although 2TS is outside the TTS of any 

nation, it falls within Philippines’ EEZ. As 

such, the Philippines enjoys sovereign 

rights under international law to explore, 

exploit, conserve, and manage natural 

resources in and around 2TS. To protect 

these sovereign rights against unlawful 

claims by the PRC, the Philippines

maintains a detachment of Marines at 

BRP Sierra Madre, which remains a commissioned vessel in the Philippine Navy.

The US has affirmed that an armed attack 

on Philippine armed forces, aircraft, or 

public vessels in the South China Sea 

would invoke U.S.–Philippines Mutual 

Defense Treaty obligations. These obligations could extend to on attack on BRP 

Sierra Madre, its Marine detachment, or a 

Philippine public vessel transiting to resupply BRP Sierra Madre.

USINDOPACOM continues to expand 

efforts with the Armed Forces of the 

Philippines (AFP) to preserve peace and 

stability and uphold international law. 

Among many efforts currently underway, 

USINDOPACOM and AFP legal advisors 

recently met in Manila to plan legal engagements and cooperation for the coming year. These activities will serve to 

strengthen collaboration between legal 

advisors, counter malign activity and legal warfare, and advance the rules-based 

international order. For additional details 

and sourcing, see J06 TACAID here. 

Source: Jay Directo/Agence France Presse – Getty & PHL 

Coast Guard

2nd Thomas Shoal: Provocations Against Philippines

I N S I D E T H I S 

I S S U E :

Protecting 

SLOCs

2

Japan and US 

Legal Dialogue

3

Australia’s 

MLS Forum

3

Partnered CLawfare at Sea 

4

US/Sri Lanka 

Building Ties

5

ROK/US Legal 

Team

5

Thailand: EX 

Cobra Gold 23

6

MILOPS 23 6

High Altitude 

Balloons

7

USINDOPACOM Office of the Staff Judge Advocate 

Legal Vigilance Dispatch

Promoting the Rule of Law to Ensure a Free and Open Indo-Pacific

I S S U E 3 , S P R I N G A P R I L 2 0 2 3

S P E C I A L 

P O I N T S O F 

I N T E R E S T :

 PRC’s provocation 

of the Philippines 

around 2TS

 US and allies capable of protecting 

SLOCs

 Multiple legal 

engagements 

across the IndoPacific

 MILOPS 23 Update

 Law relating to 

High Altitude 

Balloons
P A G E 2

U.S., Allies, & Partners Protect Chokepoints and 

Sea Lines of Communication

In the event of conflict, the United States and 

its allies and partners are willing and able to 

protect and secure chokepoints and sea lines 

of communication (SLOCs) around the world. 

Chokepoints are constricted passageways, like 

straits and canals, that separate oceans and 

seas; they are relatively narrow, heavily 

trafficked, and sometimes in regions 

vulnerable to instability. SLOCs are the 

principal maritime routes between ports used 

for trade, military, or other purposes.

The naval concept applicable to protecting 

and securing chokepoints and SLOCs is 

known as sea control. Lawful sea control helps 

to preserve freedom of navigation guaranteed 

to all nations by international law. When 

necessary during armed conflict, lawful sea 

control may deny or limit an adversary’s 

ability to threaten chokepoints and SLOCs or 

use them for war-sustaining shipping.

Sea control is a concept deeply rooted in naval 

strategy and history. U.S. maritime strategy

defines sea control as “the condition in which 

one has freedom of action...in specified areas 

and for specified periods of time and, where 

necessary, to deny or limit its use to the 

enemy.” Like the United States, Japan, South 

Korea, Australia, the United Kingdom, and 

many other allies and partners recognize the 

importance of sea control in naval strategy.

Legal vigilance enables effective sea control by 

ensuring execution in accordance with international law including the law of armed conflict. 

Legal vigilance also illuminates attempts by 

other states to exercise unlawful sea control 

through coercion and intimidation; unsafe and 

unprofessional air and sea interactions; interference with navigational rights and freedoms; 

and legally baseless and excessive maritime 

claims. 

Given the vital significance of chokepoints and 

SLOCs to the global economy, U.S. forces train 

with allies and partners to exercise lawful sea 

control in a manner that ensures critical waterways remain open for trade and freedom of 

navigation, but shielded from hostilities and 

war-supporting shipping by adversaries during potential conflict. 

USINDOPACOM Office of the Staff Judge Advocate 

Source: U.S. Navy - USN, Japanese & Canadian Forces

Source: USN CNO Navigation Plan (2022)
P A G E 3

March 15, 2023 - The Commander, U.S. Pacific Fleet (CPF) Legal Office hosted counterparts from the Japan 

Maritime Self-Defense Force (JMSDF) Maritime Staff Office for a day of legal discussions and relationshipbuilding. The meeting was part of a recurring series of legal engagements conducted between CPF and 

JMSDF legal advisors pursuant to a Memorandum of Understanding executed in 2013. The purpose of 

these continuing engagements is to foster trust and cooperation, maximize alignment on legal issues of 

common interest, and ensure interoperability in advance of coalition contingency operations in the future. 

The Spring 2023 legal dialogue addressed a number of contemporary topics, including high-altitude 

balloons, grey-zone activities, and recent developments in Japanese domestic law and policy concerning 

national security strategy and when a use of force may be appropriate. Participants also engaged in robust 

discussion regarding the PRC’s use of legal warfare to undermine the rules-based international order and 

U . S . I n d o-P a c i f i c C o m m a n d ’ s c o u n t e r-l a w f a r e i n i t i a t i v e , w i t h p a r t i c u l a r 

emphasis on the importance of ensuring a common understanding between allies on complex issues. Both 

offices resolved to continue close coordination and collaboration in their day-to-day practice. After a full 

day of weighty legal discussions at COMPACFLT, the dialogue concluded with an informal social and 

happy hour on historic Ford Island overlooking the USS Arizona Memorial. Kanpai!

Japan and U.S. Maritime Legal Dialogue

CPF-JMSDF Legal Dialogue participants gather in front of Headquarters U.S. Pacific Fleet 

USINDOPACOM Office of the Staff Judge Advocate 

Australia’s Military Legal Service Hosts Inaugural Forum

The Australian Defence Force’s 

Military Legal Service (MLS) held its 

inaugural Legal Forum in Sydney 

from Mar 29-30, 2023. The theme was: 

Legal Capability—Enabling the Joint 

Force in Peace and War. 200 MLS Legal 

Officers, including VIPs and guests 

from New Zealand, the UK and United States attended.

The MLS Forum brought together the 

ADF’s joint legal capability for the 

first time since its inception, as an 

element of Joint Capabilities Group 

and Defence Legal Division, aligning 

with Defence’s strategic direction. 

Among a variety of topics, the MLS 

Forum included discussion on the 

imperative to maintain a welldisciplined fighting force, emphasizing 

that how a nation fights can often outweigh with whom it fights.

Participants also examined legal challenges in the era of strategic competition including issues associated with 

emerging technologies and combined 

efforts to counter legal warfare.

International panel of military lawyers 

from NZDF, UK Army, and US 

INDOPACOM
Nimitz Carrier Strike Group Talks Counter-Lawfare with Allies 

P A G E 4

The Nimitz Carrier Strike Group 

conducted a trilateral maritime 

exercise with the Japan Maritime SelfDefense Force (JMSDF) and Republic 

of Korea Navy (ROKN), Apr 3-4, 2023. 

“The U.S., Japan, and Korea are three 

maritime nations with shared vision 

for a free and open Indo-Pacific by 

working together to develop mutual 

trust, partnership, and capability,” said 

Rear Adm. Christopher Sweeney, 

commander, Carrier Strike Group 11. 

In the midst of combined operations at sea (including antisubmarine exercises, search and 

rescue exercises, and staff embarkations) officers of all three 

nations took time to discuss how 

to recognize and respond to the 

PRC’s legal warfare efforts. 

During the exercise, U.S. Navy, 

JMSDF, and ROKN officers discussed USINDOPACOM’s counter

-lawfare program. This engagement was the first of its kind at 

sea, and was unique in that the 

audience consisted primarily of 

surface warfare officers from the 

three navies and focused on how all 

naval officers, not just legal advisors, must remain legally vigilant. 

“Because PRC uses law as a 

weapon, naval officers should have 

a tactical understanding of the 

challenges these legal dilemmas 

create – just as they would learn 

about any other PRC weapon system,” said Lieutenant Commander 

Dennis Harbin, staff judge advocate, Carrier Strike Group 11. 

the issue of accession to the UN 

Convention on the Law of the Sea 

(UNCLOS) and the weight of 

customary international law; and 

the importance of recording and 

reporting unsafe behaviors. 

Participants in the trilateral exercise included the aircraft carrier 

USS Nimitz (CVN 68), the Arleigh 

Opportunities to collaborate among 

like-minded allies and partners on the 

influence of law in shaping 

naval operations supports USINDOPACOM’s efforts to protect the rulesbased international order and a Free 

and Open Indo-Pacific. Discussion 

topics included collaboration between 

legal advisors and public affairs 

officers in the “battle of the narrative”; 

Burke-class guided missile destroyers USS Decatur (DDG 73) and USS 

Wayne E. Meyer (DDG 108), JS 

Umigiri (DD 158) of the JMSDF, and 

ROKS Yul Gok Yi (DDH 992), 

ROKS Dae Jo Young (DDH 977), 

ROKS Choi Young (DDH 981), and 

ROKS So Yang (AOE 51) of the 

ROKN.

USINDOPACOM Office of the Staff Judge Advocate 
P A G E 5

In February and March 2023 judge advocates assigned to U.S. Indo-Pacific Command and the Defense Institute of International Legal Studies (DIILS) supported International Human Rights Law and Law of 

Armed Conflict legal engagements in Colombo and Trincomalee, Sri Lanka. In addition to robust exchanges on the rule of law and the rules-based international order, discussions focused largely on maritime law 

enforcement, the use of force in maritime operations, defense support of civil authorities, and illegal, unreported, and unregulated fishing (IUUF). Representatives from the Sri Lankan Air Force and Navy were 

especially concerned with combatting IUUF as they regularly work together on this important issue for the 

country. The U.S. and Sri Lankan sides committed to continued legal collaboration to address matters of 

mutual interest. 

U.S. and Sri Lanka Legal Teams Build Ties

USINDOPACOM Office of the Staff Judge Advocate 

ROK - U.S. Lawyers Strengthen Alliance During Ex Freedom Shield 23

Exercise Freedom Shield took 

place from 6 March to 23 March 

2023 in the Republic of Korea 

(ROK). “Freedom” highlights 

the immutable value of the 

ROK-U.S. Alliance and “Shield” 

symbolizes the defensive nature 

of the exercise. More than 30 

U.S. judge advocates from all 

services teamed with ROK 

counterparts in delivering 

operational legal support to 

Combined Forces Command, 

U.S. Forces Korea, and United 

Nations Command on a wide 

range of issues, to include selfdefense, rules of engagement, 

laws of armed conflict, and law 

of the sea. 

Throughout the exercise, the 

R O K - U . S . l e g a l t e a m 

exemplified legal interoperability and enduring commitment 

to the rules-based international 

order. 

(Left to Right) Capt Burke (USAF), 1stLt Kim (ROK), PFC 

Ahn (ROK), LtCol Noh (ROK), MAJ Jones (USA), Maj Korges 

(USMC), CDR Ericson (USN), LtCol Eberle (USAF), LT 

Fitzpatrick (USN). 

USINDOPACOM/DIILS Instructors in 

Trincomalee, Sri Lanka. 

US Personnel: Bottom Row, Left to Right: 

LCDR Phil Brueder, (USN), LTC Steve 

Bryant (USAR), LT Chuck Ball (USN). 
P A G E 6

U.S. and Indonesian JAGs 

participating in CARAT 

December 2022.

Exercise Cobra Gold - 1st Annual Multi-National Legal Summit

UPDATE: MILOPS 23

USINDOPACOM’s 34th annual International Military Law and Operations 

(MILOPS) Conference is set to occur 

from 30 July through 3 August in Bali, 

Indonesia. This year’s conference theme 

is “Cooperating to Defend the RulesBased International Order.” 

“We are grateful to the host nation and 

our friends in the Indonesian armed forces for their support with executing MILOPS 23,” said Commander Tim Boyle, 

USINDOPACOM Chief of National Security Law. 

The MILOPS conference agenda will include keynote addresses from senior U.S. 

and host nation officials as well as 

presentations and panel discussions featuring prominent law, policy, and operations experts. Topics to be addressed 

include lessons from Russia’s invasion of 

Ukraine; implications of climate change 

on national security; illegal, unregulated, 

and reported fishing; and a range of 

threats to the rules-based international 

order in the South and East China Seas. 

Formal invitations and the official MILOPS 23 website are expected to launch 

in May. Contact j06.pacom@pacom.mil 

for questions. 

More than 7,000 military personnel took 

part in the 42nd iteration of Exercise Cobra 

Gold from 27 February to 10 March 2023 

in the Kingdom of Thailand. In addition to 

the host nation, participant nations included the United States, Indonesia, the Republic of Korea (ROK), Singapore, Japan, 

and Malaysia, with limited 

participants, planners, and observers from 

more than 20 additional nations. 

This year’s Cobra Gold featured the 

1st Annual Multi-National Legal Summit 

designed to strengthen legal partnerships 

and improve legal interoperability. Military legal advisors from Thailand, the 

United States, Singapore, Malaysia, Australia, and the ROK shared best 

practices, expanded legal networks, built 

shared legal understandings, and 

committed to work together on matters of 

mutual interest, including countering legal 

warfare and upholding the rules-based 

international order. 

USINDOPACOM judge advocates concluded the summit with a presentation 

emphasizing Commander USINDOPACOM’s vision of a Free and Open 

Indo-Pacific.

“Cobra Gold strengthens our ability to 

plan and conduct combined joint highend security peacekeeping operations 

across all domains,” Adm. John 

Aquilino, Commander, U.S. Indo-Pacific 

Command, said at the opening 

ceremony. “Through Cobra Gold we 

demonstrate our resolve to respond together to preserve a free and open IndoPacific so that all nations can maintain 

peace, stability and prosperity.”

USINDOPACOM Office of the Staff Judge Advocate 

Colonel Machica, Judge Advocate General of the Armed Forces of the Philippines (AFP), 

with Major Alferez, AFP (right) 

and Commander Emge, US 

INDOPACOM J06 (left).

Legal advisors from AFP and 

USINDOPACOM joint force 

meet during Balikatan 2023, the 

largest Philippines-U.S. combined exercise to date.
On 4 Feb 2023, the U.S. conducted a successful operation to take down a PRC high-altitude balloon (HAB) 

above its territorial sea, off South Carolina. U.S. officials stated the HAB was equipped to collect signals 

intelligence (SIGINT) for the People’s Liberation Army (PLA), and had targeted over 40 countries. The U.S. 

Congress condemned the PRC for the “brazen violation” of U.S. sovereignty and efforts to “deceive the 

international community through false claims about its intelligence collection campaigns.”

At first, the PRC implausibly characterized its HAB as a “civilian airship” used for “meteorological” 

purposes while blaming “force majeure” for “unintended entry”. Now that time has passed and the extent 

of the PRC’s HAB program is widely known, the PRC seems to have a pivoted from one-off excuses in favor 

of sowing confusion around the idea of “near space” and the false notion that international law does not 

limit State activity above altitudes at which aircraft operate. 

CNN reported that searches on CNKI, the PRC’s largest online academic database, show PRC military and 

civilian researchers have published more than 1,000 papers and reports on “near space.” Some PRCcontrolled media have even claimed that the Outer Space Treaty and its provisions on “exploration and use 

by all states” should be applied to HAB flights. 

By propagating the existence of “near space” in various publications, the PRC likely aims to foment a grey 

zone in which to execute unlawful surveillance under a veneer of legitimacy. To be clear, there is no “near 

space” in international law – only airspace and outer space. International law does not specify where airspace ends and space begins, but all proposals demarcating the airspace-outer space divide begin at 

altitudes well above where HABs operate.

Notwithstanding the PRC’s attempts to sow confusion, HABs are aircraft under international law subject to 

the rules and norms governing safety of flight and observance of national boundaries, even in uncontrolled 

airspace above altitudes at which aircraft operate. Under international law every nation has complete and 

exclusive sovereignty over the airspace above its territory. As such, all nations may take measures within 

their respective airspace to mitigate threats posed by unlawful HAB surveillance. The measures taken by 

U.S. forces to mitigate the threat posed by the PRC’s HAB were consistent with longstanding practice of 

States exercising jurisdiction in their territories and airspace in analogous circumstances. 

USINDOPACOM’s legal position regarding HABs has been consistent and transparent. As an example, 

nearly a year prior to the U.S. takedown of the PRC’s HAB, the Armed Forces of the Philippines (AFP) and 

USINDOPACOM coordinated on the use of HABs for combined maritime domain awareness during Balikatan, a large-scale bilateral exercise. AFP and USINDOPACOM ensured their cooperative use of HABs during Balikatan conformed to international law and standards governing navigational freedoms and safety of 

flight. 

Setting the Record Straight on Balloon Law

P A G E 7

USINDOPACOM Office of the Staff Judge Advocate 

On 4 Feb 2023, the U.S. conducted a successful operation to take down a PRC high-altitude balloon (HAB) 

above the territorial sea off South Carolina. U.S. officials stated the HAB was equipped to collect signals 

intelligence (SIGINT) for the People’s Liberation Army (PLA) as part of a program that had targeted over 40 

countries. The U.S. Congress condemned the PRC for the “brazen violation” of U.S. sovereignty and efforts 

to “deceive the international community through false claims about its intelligence collection campaigns.”

At first, the PRC implausibly characterized its HAB as a “civilian airship” used for “meteorological” 

purposes while blaming “force majeure” for 

“unintended entry.” Now that time has passed and the 

extent of the PRC’s HAB program is widely known, the 

PRC seems to have a pivoted from one-off attempts at 

justification in favor of a broader effort to sow confusion around the idea of “near space” and the false notion that international law does not limit State activity 

above altitudes at which aircraft operate. 

CNN reported that searches on CNKI, the PRC’s largest online academic database, show PRC military and 

civilian researchers have published more than 1,000 

papers and reports on “near space.” Some PRCcontrolled media have even claimed that the Outer 

Space Treaty and its provisions on “exploration and use by all states” should be applied to HAB flights. 

By propagating the existence of “near space” in various publications, the PRC likely aims to foment a grey 

zone in which to execute unlawful surveillance under a veneer of legitimacy. To be clear, there is no “near 

space” in international law – only airspace and outer space. International law does not specify where airspace ends and space begins, but all proposals demarcating the airspace-outer space divide begin at 

altitudes well above where HABs operate.

Notwithstanding the PRC’s efforts to create confusion around “near space,” HABs are aircraft under international law subject to the rules and norms governing safety of flight and observance of national airspace 

boundaries, even in uncontrolled airspace above altitudes at which aircraft operate. Under international law 

every nation has complete and exclusive sovereignty over the airspace above its territory. As such, all nations may take measures within their respective airspace to mitigate threats posed by unlawful HAB surveillance. The measures taken by U.S. forces to mitigate the threat posed by the PRC’s HAB were consistent 

with longstanding practice of States exercising jurisdiction in their territories and airspace in analogous circumstances. 

USINDOPACOM’s legal position regarding HABs has been consistent and transparent. As an example, 

nearly a year prior to the U.S. takedown of the PRC’s HAB, the Armed Forces of the Philippines (AFP) and 

USINDOPACOM coordinated on the use of HABs for combined maritime domain awareness during Balikatan, a large-scale bilateral exercise. AFP and USINDOPACOM ensured their cooperative use of HABs during Balikatan conformed to international law and standards governing navigational freedoms and safety of 

flight. 

Setting the Record Straight on Balloon Law

P A G E 7

Lawful use of HABs by U.S. forces in coordination with the Armed 

Forces of the Philippines during exercise Balikatan 2022. 

Image Credit: PETTY OFFICER DARBI COLSON/U.S. ARMY
(continued from page 7) USINDOPACOM coordinated extensively with AFP authorities and air traffic control to 

ensure the safety of people on the ground and civil and military aircraft operating nearby. Before the exercise, 

U.S. forces received authorization from the Philippine government to operate the HABs in Philippine national 

airspace as required by international law and Philippine domestic law. 

In a demonstration of combined commitment to upholding the rules-based international order, the legal staffs of 

USINDOPACOM and Australia’s Headquarters Joint Operation Command (HQJOC) collaborated on an August 

2022 bilateral legal memo on international law applicable to HAB operations, later receiving significant attention 

on Twitter. USINDOPACOM and HQJOC legal advisors agreed that HABs operate in airspace and do not cross 

into outer space, and that “any State’s use of HABs must conform to international rules and norms governing 

safety of flight. This includes the exercise of due regard as well as observance of boundaries of national airspace.” 

Although HABs may not be dominating the news cycle anymore, continued legal vigilance requires like-minded 

allies and partners to reject “near space” before it gains a foothold. USINDOPACOM J06 will continue to work 

together with allied and partnered legal offices to monitor evolving PRC legal warfare tactics and illuminate 

actions that undermine international law and the rules-based international order. 

For additional details and sourcing, see the INDOPACOM J06 TACAID located here. 

USINDOPACOM Office of the Staff Judge Advocate 

What is Legal Vigilance?

Legal vigilance refers to the monitoring and assessment of the 

legal environment. Maintaining legal vigilance ensures the United 

States Indo-Pacific Command (USINDOPACOM) and its allies 

and partners are able to identify threats (including “legal warfare” 

by the People’s Republic of China), integrate across the combined 

joint force, and implement action to uphold the rule of law. 

The Legal Vigilance Dispatch is an informal, non-comprehensive 

survey of open-source information on the legal environment. Unless otherwise noted, content is produced by the USINDOPACOM 

Office of the Staff Judge Advocate (OSJA) and does not necessarily 

reflect official positions of the U.S. government.

In addition to identifying threats in the legal environment, the 

Legal Vigilance Dispatch highlights cooperative efforts by the 

United States and its allies and partners to uphold the rule of law. 

USINDOPACOM OSJA is committed to building legal partnerships and working with allies and partners to preserve peace and 

stability in the Indo-Pacific. If you have comments, feedback, or 

vignettes to share, please contact us.

U.S. Indo-Pacific Command

Joint Operational Law Team

Office of the Staff Judge Advocate

Camp H.M. Smith

Hawaii, United States

Phone: (808) 477-6378

Email: j06.pacom@pacom.mil

Web: www.pacom.mil

Promoting the Rule of Law to Ensure a 

Free and Open Indo-Pacific