In April, I laid a wreath at the Manila American Cemetery, in the Philippines, where some 17,000 Americans are buried. Looking up at the mosaic maps of battles whose names still echo throughout the U.S. Department of Defense—Guadalcanal, Midway, Leyte Gulf, and more—it is hard not to appreciate the essential role that the U.S. military has long played in the Asia-Pacific. Many of the individuals buried in the cemetery helped win World War II. For the people and nations of the region, they also won the opportunity to realize a brighter future.

Since World War II, America’s men and women in uniform have worked day in and day out to help ensure the security of the Asia-Pacific. Forward-deployed U.S. personnel in the region—serving at Camp Humphreys and Osan Air Base in South Korea, at the Yokosuka naval base and Yokota Air Base in Japan, and elsewhere—have helped the United States deter aggression and develop deeper relationships with regional militaries. The thousands upon thousands of sailors and marines aboard the USS John C. Stennis, the USS Blue Ridge, the USS Lassen, and other ships have sailed millions of miles, made countless port calls, and helped secure the world’s sea-lanes, including in the South China Sea. And American personnel have assisted with training for decades, including holding increasingly complex exercises with the Philippines over more than 30 years.

We plan to do more, not less, in the Asia-Pacific for decades to come.

Every port call, flight hour, exercise, and operation has added a stitch to the fabric of the Asia-Pacific’s stability. And every soldier, sailor, airman, and marine has helped defend important principles—such as the peaceful resolution of disputes, the right of countries to make their own security and economic choices free from coercion, and the freedom of overflight and navigation guaranteed by international law.

Ensuring security and upholding these principles has long been U.S. policy. During Democratic and Republican administrations, in times of surplus and deficit, and in war and peace, the United States has played a part in the region’s economic, diplomatic, and security affairs. This engagement has persisted despite frequent predictions that the United States would cede its role as the main underwriter of security in the Asia-Pacific.

The results have been extraordinary: the Asia-Pacific has long been a region where every nation has the opportunity to thrive. Indeed, economic miracle after economic miracle has occurred there. Japan, South Korea, Taiwan, and the countries of Southeast Asia have all risen and prospered, and China and India are now doing the same. Human progress has produced enormous gains, as education has improved and democracy has taken hold. And compared with many other regions in recent decades, the Asia-Pacific has experienced more stability and peace.

In light of the Asia-Pacific’s progress and all the economic, political, and military changes it has produced, U.S. President Barack Obama announced in 2011 that he had “made a deliberate and strategic decision—as a Pacific nation, the United States will play a larger and long-term role in shaping this region and its future.” The so-called rebalance to the Asia-Pacific sought to reenergize the United States’ economic, diplomatic, and military engagement there. After a decade of counterterrorism and wars in the greater Middle East, the United States—and the Department of Defense—would shift its investments, commitments, and operations to the Asia-Pacific. Five years on, as the Defense Department operationalizes the latest phase of the rebalance, it is important to review the progress we have made as the United States works to ensure that the Asia-Pacific remains a region where everyone can rise and prosper.

A CHANGING REGION

The Asia-Pacific is increasingly becoming the world’s economic, political, and military center of gravity. The population changes alone are staggering: already, more than half of humanity lives in the region, and by 2050, four Asian countries—India, Indonesia, the Philippines, and Vietnam—are expected to have grown by approximately 500 million people in total. Despite some recent projections of reduced growth, the Asia-Pacific remains a key driver of the global economy and an indispensable market for American goods. The region is already home to some of the world’s largest militaries, and defense spending there is on the rise. Preserving security amid all this change is a priority for the United States and many other nations, since these dynamics are producing opportunities not only for greater growth and progress but also for greater competition and confrontation. And so the rebalance was designed to ensure the continued stability and progress of this unique region at a time of change.

To do so, Washington is strengthening economic ties with the region because the economic destinies of the United States and the Asia-Pacific are intertwined. As Asian economies continue to grow, the United States wants to reinforce the open and inclusive approach that has benefited so many in the region. Thus, one of the most important initiatives of the rebalance is the Trans-Pacific Partnership, or TPP, which aims to bind the United States more closely together with 11 other economies, guarantee a trading system with high standards, and support American exports and higher-paying American jobs. The TPP is an opportunity that the United States—and Congress—should not miss.

Carter in the Philippines, April 2016. EZRA ACAYAN / REUTERS

Through the rebalance, the United States has also reenergized its diplomacy in the region. In addition to increased visits to the region by the president and his cabinet, the United States is playing a critical role in the conversations that are helping determine the Asia-Pacific’s economic, political, and security future. And in many cases, the United States has hosted these talks. For example, in February, Obama hosted the first-ever U.S.-based leaders’ summit of the Association of Southeast Asian Nations (at Sunnylands, in California), and in September, I hosted the ten defense ministers of ASEAN in Hawaii to discuss regional security challenges.

The Pentagon is operationalizing the military part of the rebalance to ensure that the United States remains the primary provider of regional security for decades to come. The first phase of the rebalance sought to enhance the U.S. military’s force posture so that the United States continues playing a pivotal role from the sea, in the air, and underwater. It also sought to make our posture in this vast region more geographically distributed, operationally resilient, and politically sustainable. The Defense Department has committed to homeporting 60 percent of its naval and overseas air assets in the region. It has also announced plans to modernize its existing footprint in Japan and South Korea. And while maintaining a robust presence in Okinawa, Japan, it began to realign U.S. marines from a highly centralized posture there to additional locations, including Australia, Guam, and Hawaii (with Guam serving as a strategic hub).

In the rebalance’s second phase, which I launched last year, the Pentagon is continuing to place some of our best military personnel in the region and deploying some of our most advanced capabilities there. Those capabilities include F-22 and F-35 stealth fighter jets, P-8A Poseidon maritime patrol aircraft, V-22 Ospreys, B-2 bombers, and our newest surface warfare ships. The Defense Department is also devoting resources to new capabilities critical to the rebalance. We are increasing the number of surface ships and making each of them more lethal, and we are investing in Virginia-class submarines, advanced undersea drones, the new B-21 long-range strike bomber, and state-of-the-art tools for cyberspace, electronic warfare, and space.

The Defense Department is also developing innovative strategies and operational concepts and practicing these new ideas in training exercises, both on our own and with partners. For example, this past summer’s Rim of the Pacific (RIMPAC) multilateral maritime exercise—which occurs every two years and is the largest of its kind in the world—brought together 26 countries to work to promote open sea-lanes. In a remarkable show of cooperation, the United States and China even sailed together from Guam to Hawaii for the exercise, conducting several practice events along the way, including one to enhance search-and-rescue capabilities.

STRENGTHENING DEFENSE RELATIONSHIPS

As RIMPAC demonstrates, the United States’ defense relationships with allies and partners form the foundation of its engagement in the Asia-Pacific. These ties have been nurtured over decades, tested in crisis, and built on shared interests, values, and sacrifice. Under the rebalance, the Defense Department is modernizing these alliances and partnerships to ensure that they will continue to serve as the bedrock of the region’s stability and prosperity.

In East Asia, the U.S.-Japanese alliance remains the cornerstone of Asia-Pacific security. And with the new defense guidelines that Washington and Tokyo signed last year, the alliance has never been stronger or more capable of contributing to security around the region and beyond. Updated for the first time since 1997, the guidelines take new trends and technologies into account and enable U.S. and Japanese forces to work together more closely and on a wider range of contingencies—including those below the threshold of conflict and those in space and cyberspace.

The U.S.–South Korean alliance took a major step forward in 2014, when the two countries agreed to a conditions-based, rather than timeline-based, approach to determining when South Korea would obtain operational control of alliance forces in the event of a war. And in July of this year, as part of an effort to defend against North Korean ballistic missiles, our two countries decided to deploy an advanced missile defense battery, called THAAD (Terminal High Altitude Area Defense), in South Korea at the earliest possible date. The U.S.-Australian alliance, for its part, is becoming more and more a global one. The two countries are continuing their close defense cooperation not only across the region, including through a bilateral force posture initiative, but also outside the region, in the fight to accelerate the defeat of the Islamic State, or ISIS.

The Asia-Pacific is increasingly becoming the world’s economic, political, and military center of gravity.

As Obama has made clear, the U.S. commitment to the Philippines is ironclad. Under the rebalance, the alliance has made great strides. U.S. and Philippine personnel regularly train together, and thanks to the landmark Enhanced Defense Cooperation Agreement, signed in 2014, the U.S. military will help modernize the Philippine armed forces. Meanwhile, through the U.S.-Thai alliance—one of the United States’ oldest in the region—the United States is helping Thailand better defend itself.

Beyond alliances, the United States is also deepening its partnerships with friends across the region. For example, the U.S.-Indian relationship is destined to be one of the most significant partnerships of the twenty-first century. The United States and India are two great nations that share much in common: democratic governments; multiethnic and multicultural societies with a commitment to individual freedom and inclusivity; and growing, innovative, and open economies. In June, the White House recognized India as a “major defense partner,” a designation that will facilitate defense trade and technology sharing with the country on a level that the United States reserves for its closest friends and allies.

As part of what I have called a “strategic handshake”—with the United States reaching west in its rebalance and India reaching east in its Act East policy—the two countries are undertaking military exercises and strengthening the bilateral security relationship to face common challenges. There’s also a technological handshake between the two countries’ militaries. Four years ago, the United States and India created the Defense Technology and Trade Initiative to take advantage of both countries’ industrial and technological capabilities, a program that dovetails with Prime Minister Narendra Modi’s “Make in India” campaign, which is aimed at boosting domestic production. As a result, the two countries are starting to jointly develop and produce a wider range of defense projects.

The rebalance has also helped the United States develop deeper partnerships across Southeast Asia. Obama’s historic visit to Hanoi in May was just the latest demonstration of how dramatically the U.S.-Vietnamese partnership has been strengthened: the United States has lifted the ban on lethal weapons sales to Vietnam, which will help the country’s military get the equipment it needs. The U.S.-Singaporean relationship also continues to grow. In December 2015, the two countries signed the Enhanced Defense Cooperation Agreement. In addition, the U.S. Navy sent P-8A Poseidon maritime patrol aircraft on their inaugural rotation to Singapore, where we will also deploy up to four U.S. littoral combat ships on a rotating basis. Meanwhile, the United States is working with Indonesia and Malaysia to help them even better meet their own security challenges and to promote regional security.

The rise of China, of course, is also having a profound impact on the Asia-Pacific. The United States welcomes the emergence of a peaceful, stable, and prosperous China that plays a responsible role in and contributes to the region’s security network. Many countries seek beneficial and productive relationships with China, but concerns are growing about some of its actions and its willingness to accept regional friction as it pursues its self-interest. Although China has long benefited from the regional principles and systems that others, including the United States, have worked to establish and uphold, with its actions on the seas, in cyberspace, in the global economy, and elsewhere, Beijing sometimes plays by its own rules and undercuts those principles.

China’s model is out of step with where the Asia-Pacific wants to go; it reflects the region’s distant past, rather than the principled future the United States and many others want, and its approach is proving counterproductive. China’s actions are excluding it from the rest of the Asia-Pacific—erecting a Great Wall of self-isolation—at a time when the region is coming together economically, politically, and militarily to promote shared interests and a principled order. As a result, countries across the region are voicing concerns—publicly and privately, at the highest levels, in regional meetings, and in global forums—about China’s actions.

The United States remains committed to working with China to ensure a principled future for the region. The two countries have a long-standing military-to-military relationship. The U.S. and Chinese militaries recently completed two confidence-building measures, one on maritime rules of behavior and another on crisis communications, and we regularly participate together in multilateral exercises. Through these actions, our two countries have made great strides in forging more and better communication channels and reducing the risk of miscalculations that could lead to crises.

Japanese Prime Minister Shinzo Abe and U.S. President Barack Obama in Manila, November 2015. JONATHAN ERNST / REUTERS

DEVELOPING A PRINCIPLED SECURITY NETWORK

The rebalance to the Asia-Pacific will also help the United States play a critical role in the region’s developing security network. This in itself is another change for such a dynamic region: unlike elsewhere in the world, in the Asia-Pacific, a formal regionwide structure, akin to NATO in Europe, has never taken responsibility for promoting peace and stability. That has made sense given the Asia-Pacific’s unique history, geography, and politics. Yet as the region becomes more politically and economically interconnected, its militaries are also coming together to plan together, train together, and operate together more than ever before.

The growing Asia-Pacific security network weaves every state’s relationships together to help their militaries do more, over greater distances, more efficiently. It allows countries to take coordinated action in response to humanitarian crises and natural disasters, address common challenges such as terrorism, and ensure the security of and equal access to the commons, including vital waterways. Recent examples of this networked approach can be seen in collective responses to Typhoon Haiyan in 2013 and the Nepalese earthquake of 2015.

Most important, this is what I call a “principled and inclusive security network.” It is inclusive, because any nation and any military—no matter its capabilities, budget, or experience—can contribute. Everyone gets a voice and no one is excluded, and hopefully no one chooses not to participate. As this security network reflects the principles that its members have upheld for decades, it will help them realize the principled future that many in the region have chosen.

By sharing the burden for regional stability, this network represents the next wave in Asia-Pacific security. To help lead it, the United States is bringing its unique capabilities, experience, and influence to bear. For example, the Defense Department is implementing the Southeast Asia Maritime Security Initiative, an initial $425 million, five-year U.S. commitment to build maritime domain awareness and security in Southeast Asia. More than simply providing money or hardware, this initiative will help Indonesia, Malaysia, the Philippines, Thailand, and Vietnam work with one another and with the United States so that everyone can see more, share more, and do more to ensure maritime security in the region’s vital waters.

China’s model is out of step with where the Asia-Pacific wants to go.

The Asia-Pacific security network is developing in three additional ways. First, some pioneering trilateral mechanisms are bringing together like-minded countries that previously cooperated only bilaterally. The U.S.–Japanese–South Korean partnership helps coordinate responses to North Korea’s nuclear and missile provocations, and earlier this year, the trio conducted its first-ever trilateral ballistic missile warning exercise. For the past three years, the United States, India, and Japan have conducted the Malabar naval exercise together, showcasing how yet another trilateral relationship is starting to provide practical security cooperation that spans the region. And starting last November, the United States and Thailand brought Laos into a successful program on the disposal of explosive ordnance, and now the three are training together to eliminate this danger.

Second, many Asia-Pacific countries are cooperating on their own, without the United States. India has ramped up its military’s training with Vietnam’s military and coast guard. Australia, India, and Japan held a trilateral dialogue last year, marking a welcome addition to the region’s security network. Japan is also working to build the capacity of the Philippine maritime forces. And this year, Indonesia, Malaysia, and the Philippines agreed to conduct joint counterpiracy patrols.

Third, and even more broadly, many countries in the region are creating a multilateral security architecture through the ASEAN Defense Ministers Meeting–Plus. This initiative, which convenes the defense ministers of all ten ASEAN members plus those of eight other countries, fills the growing need for an action-oriented, ASEAN-centric institution that builds trust and facilitates practical security cooperation.

The principled security network is not developing in response to any particular country. Rather, it demonstrates that the region wants cooperation, not coercion, and a continuation of, not an end to, decades of peace and progress. More important, since this network is not closed, nations can more easily work together. For example, although the United States and other nations have some disagreements with China, they are committed to working through these problems, bilaterally and through the network, in ways that do not destabilize the region.

The network will also help ensure stability amid a number of security challenges. North Korea continues its provocative behavior. Violent extremism has been no stranger to the Asia-Pacific over the past several decades, and terrorist organizations, including ISIS, continue to operate in countries throughout the region. The heavily traveled Asia-Pacific sea-lanes make attractive targets for pirates seeking to steal goods or hold ships and crews for ransom. And already prone to earthquakes and volcanoes as part of the Ring of Fire, the Asia-Pacific also regularly suffers from devastating storms, worsened by accelerating climate change.

And then there are the challenges unique to this region, including those resulting from its changing economic, political, and military dynamics. Thanks to coercive actions by some states, most notably China, contentious and long-running regional disputes, particularly at sea, have grown more tense in recent years. Indeed, in the South China Sea, a transit route for approximately 30 percent of the world’s maritime trade last year, including about $1.2 trillion in ship-borne trade bound for the United States, there is a growing risk to the region’s prosperous future.

The United States is not a claimant in the current maritime disputes in the Asia-Pacific, and it takes no position on which party has the superior sovereignty claim over the disputed land features. But Washington supports the peaceful resolution of disputes, especially through mechanisms such as international arbitration. It sees the July ruling by the Permanent Court of Arbitration on maritime claims and activities in the South China Sea as an opportunity for the region to recommit to a principled future, to renewed diplomacy, and to lowering and resolving tensions rather than raising them. The U.S. military will also continue to fly, sail, and operate wherever international law allows, will continue to stand with its allies and partners in upholding core principles such as freedom of navigation and overflight, and will continue to ensure that these core principles apply equally in the South China Sea as they do everywhere else. Only if everyone plays by the same rules can the region avoid the mistakes of the past, when countries challenged one another in contests of strength and will, with disastrous consequences for humanity.

The U.S. Navy guided-missile destroyer USS Lassen in the Pacific Ocean, October 2015. US Navy / CPO John Hageman / Handout via Reuters / File Photo

SUPPLYING THE OXYGEN

The rebalance made sense for the United States when it was announced in 2011, but what has become clear since then, especially to U.S. officials traveling in the Asia-Pacific, is that it makes as much sense for the region’s people, militaries, and nations. On each of my trips to the region as secretary of defense, one thing has remained constant: requests from defense counterparts and national leaders for the United States to do more, not less, in the region. As has long been said of the Asia-Pacific, security is like oxygen: when you have enough of it, you pay no attention to it, but when you don’t have enough, you can think of nothing else. For more than 70 years, U.S. service members have helped provide the oxygen—the security that allows hundreds of millions of people around the world to feel safe, raise their children, dream their dreams, and live full lives.

Thanks to the investments and planning of the first two phases of the rebalance, the United States will have the tools it needs to continue playing this role in the Asia-Pacific. And in the next phase, the Defense Department will work to strengthen the region’s emerging principled security network through more frequent and more complex training and exercises. The Defense Department will also continue to qualitatively upgrade the United States’ force posture in the region and prioritize “big bet” investments in advanced technologies. By working within the region’s principled security network and on its own, the United States will continue to demonstrate to its allies, its partners, and the region at large that it plans to do more, not less, in the Asia-Pacific for decades to come.

With the rebalance, the United States is ensuring that its military is well positioned to help transform an era of historic change into one of historic progress. By operationalizing the rebalance, and by supporting the region’s growing principled security network, the Defense Department can help ensure that the next 70 years in the region are as secure, stable, and prosperous as the last.