It recently made headlines that NATO is not obligated to defend Hawaii, Guam, the Commonwealth of Northern Mariana Islands (CNMI), American Samoa, or other parts of the United States in the Pacific. But that doesn’t leave America alone in its Pacific defense. It has other treaty allies who can pitch in when push comes to shooting. That’s one reason why the first U.S.-Japan-Philippines trilateral meeting in DC this week is so important.

Why No NATO?

But first, what’s up with NATO? Well, one clue is in the name. It’s the North Atlantic Treaty Organization. When the treaty was agreed upon in 1949, several European countries still had colonies scattered around the planet, and the United States wasn’t keen on getting embroiled in a war on behalf of, for example, Portuguese Timor.

Accordingly, Article 6 of the NATO Treaty specified the geographic area of mutual defense as covering the territory of any NATO member in Europe or North America, the Algerian Departments of France, the territory of Turkey, and the islands under the jurisdiction of any NATO member in the North Atlantic north of the Tropic of Cancer.

Hawaii is not considered part of North America, nor are Guam, CNMI, or American Samoa. The U.S. Virgin Islands are south of the Tropic of Cancer, so they aren’t covered by NATO, either. 

However, no other NATO members, including the United States, are obligated to defend French Polynesia, the Pitcairn Islands (United Kingdom), or the Caribbean Netherlands.

That’s why, for example, when Argentina attacked Britain’s Falkland possessions in 1982, there was no obligation for the United States to come to its aid.

Who You Gonna Call?

For many years, except for a potential fight on the Korean Peninsula, nobody paid much attention to the idea that the United States might need some real help to defend itself, its interests, and its friends in the Asia-Pacific region. Yes, some bases and access might be helpful, but in a fight, it was thought that the Americans could handle anything that might come along.

Those days are over, and the idea that America’s allies must do more to defend themselves and pitch in alongside U.S. forces is de rigueur.

In the years following the establishment of NATO, the United States created a network of allies in the Pacific through mutual defense treaties, some of which could be called on to help in case of an attack on Pacific America.

The treaties mentioned here explain that an armed attack “on either of the Parties would be dangerous to its own peace and safety and declares that it would act to meet the common dangers in accordance with its constitutional processes.”

What changes is the geographic area covered by the agreements. Let’s go through them chronologically.

Philippines-U.S. Treaty (1951)

In the case of the Philippines, “an armed attack on either of the Parties is deemed to include an armed attack on the metropolitan territory of either of the Parties, or on the island territories under its jurisdiction in the Pacific.”

This means the Philippines could come to the aid of the United States not only in the case of an attack on Guam, CNMI, Hawaii, or American Samoa but even Cleveland. This is all the more reason to ensure that the Philippines is well-defended, well-armed, and well-disposed towards the United States—another reason for the United States to help with resupplying Second Thomas Shoal.

Australia-New Zealand, United States (ANZUS) Security Treaty (1951)

ANZUS is a bit of a misnomer because New Zealand was suspended from the treaty in 1986 after it declared itself a nuclear-free zone and refused to let in nuclear-armed or nuclear-powered ships. It still holds for Australia and the United States, though.

In wording that might sound familiar, the treaty states: “An armed attack on any of the Parties is deemed to include an armed attack on the metropolitan territory of any of the Parties, or on the island territories under its jurisdiction in the Pacific.” So, the same extensive range as the Philippines. Cleveland is still protected.

South Korea-U.S. Treaty (1953)

South Korea is more restricted. The treaty covers “an armed attack in the Pacific area on either of the Parties in territories now under their respective administrative control, or hereafter recognized by one of the Parties as lawfully brought under the administrative control of the other.”

So, this should cover Guam, CNMI, Hawaii, American Samoa, and other parts of Pacific America, but the American mainland is on its own.

Japan-U.S. Treaty (1960)

Japan is different, in part because it wasn’t really supposed to re-militarize in 1960 when the treaty was signed. Until recently—except for its navy—Japan’s military was not taken too seriously, and many U.S. officers, including some senior ones, reckoned the Japanese could sit events out. The Japanese were largely happy with leaving things up to the Americans.

That started to change in the late 2000s, as more Americans realized they needed help dealing with an increasingly powerful and assertive China.

So, what does the treaty say? “Each Party recognizes that an armed attack against either Party in the territories under the administration of Japan would be dangerous to its own peace and safety and declares that it would act to meet the common danger in accordance with its constitutional provisions and processes.”

This means Japan is only obligated to come to the defense of the United States if U.S. military bases are attacked in Japan. Around 2010, the commander of Marine Forces Pacific visited Japan, and while speaking to the media, he actually read the treaty out loud. He summed up its terms as “I’ve made a promise to defend you…but you haven’t made a similar promise to me.” This resonated with the assembled press.

That said, Japan is much more serious about its role in the region now, and the upcoming trilateral meeting between the United States, Japan, and the Philippines could result in something interesting.

Thailand-U.S. Ties

Thailand is often mentioned as the fifth U.S. treaty ally in the Pacific. Still, its agreement(s) are vague and, as with the Thanat-Rusk Communiqué (1962), seem more geared towards reassuring Thailand that the United States will come to its aid rather than getting Thailand to agree to defend Pacific America.

The Bottom line

While the treaties allow its signatories “outs” via, for example, “constitutional processes,” in the cases of the Philippines, Australia and South Korea, Guam, CNMI, Hawaii, and American Samoa are covered. It’s also worth noting that the Philippines, Australia, South Korea, and Thailand all provided some form of support to the United States during the Vietnam War. And Japan has been much more vocal about wanting to contribute to regional defense. 

So, while it would be helpful to get some support from NATO if Pacific America was attacked—say even a mutual commitment to cut economic ties with the aggressor—the United States doesn’t stand alone in the Pacific. This is all the more reason to ensure America’s friends have what they need to defend themselves—and America.

Cleo Paskal is a Non-Resident Senior Fellow with the Foundation for Defense of Democracies. Follow her on X: @CleoPaskal. 

Col. Grant Newsham (USMC—Ret.) is the former U.S. Marine Attaché at the U.S. Embassy in Tokyo and the author of When China Attacks: A Warning to America. Follow him on X: @NewshamGrant.

Image: Shutterstok.com.