By Murray Hiebert

President Barack Obama will host leaders from the 10 ASEAN countries for a summit at the lush Sunnylands retreat in southern California on February 15 and 16 in a gesture aimed at deepening U.S. ties to this dynamic region. The president raised the idea of the meeting with Southeast Asian leaders at the U.S.-ASEAN Summit in Kuala Lumpur in November 2015, during which he and his ASEAN counterparts announced the upgrading of U.S.-ASEAN relations to a strategic partnership. The leaders will look to flesh out the ASEAN-U.S. Plan of Action 2016–2020 that they endorsed at the summit in Kuala Lumpur.

Southeast Asia has been a focal point of the U.S. rebalance to Asia, which was announced soon after Obama took office in 2009. The Sunnylands venue is intended to provide a more relaxed atmosphere than a formal summit in Washington would. Ironically, this is the same retreat center where Obama hosted Chinese president Xi Jinping in 2013; the upcoming summit is likely to keep China on its toes, as Beijing is vying with Washington for influence and hearts and minds in Southeast Asia.

U.S. officials say the president is looking to bolster economic, political, security, and people-to-people ties with the region when he meets the ASEAN leaders.

Washington often finds it difficult to cobble together projects that work for everyone in this eclectic grouping of countries. Economically, Singapore pursues free market principles while Indonesia is highly protectionist. Myanmar and Laos are among the poorest nations in Asia, while Singapore is one of the wealthiest on the planet. Cambodia and Laos are traditionally closer to China, while the Philippines and Vietnam have sought closer ties with the United States to hedge against China’s assertiveness in the South China Sea.

Economically, Southeast Asia is critical to U.S. companies. Two-way trade in goods and services reached $254 billion in 2014, making Southeast Asia the United States’ fourth-largest trading partner. The stock of U.S. foreign direct investment totaled $226 billion in 2014, making U.S. companies the single largest group of investors in the region.

The Southeast Asian nations launched the ASEAN Economic Community (AEC) on January 1, with the ultimate goal of moving toward a common economic market and production platform in the years ahead. Four of the countries—Brunei, Malaysia, Singapore, and Vietnam—are members of the just-completed Trans-Pacific Partnership (TPP) trade pact that also includes the United States. The Philippines, Indonesia, and Thailand have expressed interest in joining the trade arrangement in a future tranche.

In the words of a respected ASEAN ambassador, Washington can become the region’s leading economic partner by knowing how to combine the longer-term vision of the U.S. government with the strengths and short-term objectives of the U.S. private sector. Since the AEC is seen by regional governments as a turning point for ASEAN, U.S. government agencies should pursue capacity-building projects for less developed countries such as Cambodia, Laos, and Myanmar to help them complete their commitments under the AEC. Areas could include customs and trade facilitation, harmonization of standards, the digital economy, and increased capacity by small- and medium-sized enterprises.

The United States in late 2014 proposed hammering out a nonbinding set of investment principles with ASEAN, a project that quickly withered because Indonesia opposed the proposal. This idea might be resurrected at Sunnylands because these principles could form the basis of a TPP investment chapter down the road. And if some countries are not ready to join these talks, Washington might want to discuss charging ahead with a “coalition of the willing” within ASEAN, which would be open to the remaining countries when they are ready.

Maritime security will be another important focus in Sunnylands. Four ASEAN countries—Brunei, Malaysia, the Philippines, and Vietnam—are in a dispute with China in the South China Sea, where Beijing has built several artificial islands, three of which boast airstrips capable of accommodating military planes. This recent construction, coupled with concerns about possible militarization of the reclaimed features in the Spratly Islands, will likely feature high on the summit agenda.

With the Permanent Court of Arbitration in The Hague expected to issue a verdict on Manila’s case against Beijing in the South China Sea around mid-year, Obama will want to use the summit to discuss the need for a united front within ASEAN after the tribunal makes its ruling. It is unrealistic to expect a full-throated endorsement by all ASEAN members, but it will be crucial that the grouping issue a statement (or at least include language in the chairman’s statement at a subsequent summit) acknowledging the ruling, supporting the right of ASEAN members to resort to arbitration, and calling on all parties to pursue legal and peaceful means in their search for a resolution.

At the same time, Obama will need to strike a balance between providing much needed U.S. leadership on the South China Sea issue and showing support for the role of ASEAN and ASEAN-driven mechanisms, including talks between ASEAN and China toward a Code of Conduct on the South China Sea.

Obama will want to provide more clarity about the $250 million Southeast Asia Maritime Security Initiative, which Defense Secretary Ashton Carter first announced at the Shangri-La Dialogue in Singapore in May 2015, to bolster the naval and coast guard capabilities of Indonesia, Malaysia, the Philippines, and Vietnam. He should also clarify the role of the South China Sea Initiative outlined in the 2015 National Defense Authorization Act, which authorizes the United States to assist Brunei, Indonesia, Malaysia, the Philippines, Singapore, Taiwan, and Vietnam to boost their maritime security and maritime domain awareness in the South China Sea. The president could also try to build support for more formal intelligence sharing within Southeast Asia to further boost maritime domain awareness and regional maritime security cooperation.

Washington could reiterate Kuala Lumpur’s call for more regional navies to use the Code for Unplanned Encounters at Sea, which the United States signed with 24 other Asia-Pacific countries in Qingdao, China, in 2014. Obama could also use the summit to encourage more Southeast Asian countries to participate in the Japanese Maritime Self Defense Force’s ship rider exchange program—of which Malaysia is already a member and to which the Chinese navy also contributes—in order to boost mutual trust and build confidence among regional navies. Washington stands to benefit from a more consolidated security role played by Tokyo, a crucial regional U.S. ally, in Southeast Asia.

Mr. Murray Hiebert is a senior fellow and deputy director of the Chair for Southeast Asia Studies at CSIS. Follow him on twitter @MurrayHiebert1.