In his more than three years as Philippine president, Rodrigo Duterte has made a habit of casting doubt on the future of his country’s longstanding defense ties with the U.S., usually in response to U.S. concerns about his deadly drug war. Now he’s taken the first step, having served notice that he intends to terminate the Visiting Forces Agreement next year. But whether he he has the constitutional authority to make such a move without Congress is a question pending before the nation’s highest court.

1. What defense agreements are there?

There are three:

• The Mutual Defense Treaty was signed in 1951, five years after the U.S. granted the Philippines independence, and it has been at the center of defense relations ever since. The eight-article pact -- one of seven collective defense treaties the U.S. has globally -- calls for each side to help build defense capabilities and “meet the common dangers in accordance with its constitutional processes” if either side is attacked.

• The Visiting Forces Agreement, signed in 1998, spells out the legalities for U.S. military personnel operating in the Philippines. It covers everything from passport regulations to procedures for importing military equipment to criminal jurisdiction.

• The Enhanced Defense Cooperation Agreement, signed in 2014, allows for a greater U.S. presence at Philippine military bases and the construction of new facilities there.

2. What are Duterte’s issues with them?

The president has questioned whether the U.S. would defend the Philippines if China seizes disputed shoals and reefs in the South China Sea -- skepticism that has persisted for decades. A U.S. diplomatic cable from 1976, since declassified, states the Mutual Defense Treaty doesn’t cover disputed areas such as the Spratly Islands. U.S. Secretary of State Michael Pompeo said last year the treaty would apply if Philippine vessels or planes were attacked in the South China Sea. But Duterte’s government wants more clarity, with Defense Secretary Delfin Lorenzana saying the treaty’s ambiguity “will cause chaos and confusion during a crisis.” Duterte also has said military deals with the U.S. haven’t helped address security threats in the Philippines, particularly the communist insurgency. And he frequently lashes out at the U.S. over what he perceives as its hypocrisy and meddling, and has sought to improve relations with Beijing despite their territorial disputes.

3. What would it take to withdraw?

While the Philippine Constitution requires at least two-thirds of senators to vote to approve an international treaty, it is silent on ending one. The Supreme Court is considering whether Duterte has the power to end treaties himself or if Congress should be involved -- an issue that goes back to his unilateral decision in 2018 to withdraw from the International Criminal Court over its investigation of his war on drugs. Duterte and his allies in Congress say he has the power, but in any case it would take a while:

• The Mutual Defense Treaty states it may be terminated by either side one year after notice has been given to the other party. What counts as “notice” is unclear. It was ratified by the Senate of each country.

• The Visiting Forces Agreement is seen as an official treaty in the Philippines because it was approved by the Senate, and as an executive agreement in the U.S., which means it didn’t require ratification. It states it can be ended with 180 days notice given in writing to the other party.

• The Enhanced Defense Cooperation Agreement is considered an executive agreement by both sides, signed by the Obama administration with President Benigno Aquino, Duterte’s predecessor. It has an initial term of 10 years, though it remains in force unless either side terminates it with a year’s written notice.

4. What’s the impact now?

We don’t know yet. The two militaries conduct joint exercises annually. Foreign Affairs Secretary Teodoro Locsin said scrapping the military deal may also dilute U.S. commitment to other pacts, affect trade relations and make it more difficult for the Philippines to access millions of dollars in U.S. defense aid.

5. Has this happened before?

The Philippines has periodically reassessed its relationship with the U.S., which ruled the Southeast Asian nation as a territory for nearly 50 years after it was ceded by Spain. After World War War II, Clark Air Base and Subic Bay Naval Base, near Manila, were the largest U.S. military outpost in the Western Pacific. The 1947 Military Bases Agreement, originally a 99-year deal, was revised several times to give the Philippines more compensation or sovereignty. An amendment was added that allowed for it to end in 1991. As the deadline approached, leaders from both countries sought to extend the pact. Yet an upswell of anti-colonial sentiment prompted the Philippine Senate to reject a fresh agreement, and the U.S. closed all of its bases by 1992.

• QuickTakes on Duterte and his war on drugs.

• Bloomberg Graphics looks at Philippine political dynasties and the silent war in the South China Sea.

• Stars and Stripes reported on a new facility opened in 2019.

• Bloomberg Opinion’s Hal Brand sees the Philippines as a battleground in the U.S-China sparring.

(Norman P. Aquino and Chris Blake contributed to an earlier version of this story.)

To contact the reporter on this story: Andreo Calonzo in Manila at acalonzo1@bloomberg.net

To contact the editors responsible for this story: Cecilia Yap at cyap19@bloomberg.net, Ruth Pollard, Paul Geitner

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