Sailing Together or Ships Passing in the Night?India and the United States in Southeast Asia Walter C. Ladwig III (bio) and Anit Mukherjee (bio) keywords india, united states, southeast asia, security architecture [End Page 51] executive summary This article examines the significant congruence of U.S. and Indian interests in Southeast Asia and assesses both the prospects and constraints that New Delhi and Washington face in coordinating their policies toward the region. main argument Political leaders and analysts have described U.S.-India relations as a global partnership with the potential to shape the future security architecture of the Indo-Pacific. As is widely acknowledged, the two countries' extraregional interests align most closely in Southeast Asia. Accordingly, this article examines the potential for and limitations of U.S. and Indian cooperation in the region to achieve shared aims. Extensive diplomatic consultations between the two countries have led to a significant convergence in their positions on regional security challenges. Active cooperation, however, remains constrained by a number of factors, including India's need to prioritize foreign policy challenges closer to home, concerns about provoking China, and a discomfort among countries in Southeast Asia regarding the idea of a joint U.S.-India approach toward the region. Due to these limitations, U.S.-India policies in Southeast Asia are expected to continue to operate in parallel instead of becoming a joint endeavor. policy implications • The U.S. and India, which are at the initial stages of a cooperative approach to Southeast Asia, should intensify their diplomatic and military exchanges and establish a dedicated forum to share views and information on political and security developments in the region. • Strengthening the regional security architecture should be a major focus of Indo-U.S. efforts in Southeast Asia. In particular, they should concentrate on assisting the creation of a region-wide maritime domain awareness system, as well as working in parallel to develop the capacity of partner militaries. • Connectivity and infrastructure projects should be a renewed focus of Indian and U.S. efforts in the region, in partnership with like-minded third countries such as Japan. [End Page 52] The transformation in U.S.-India relations from alienation during the Cold War to a robust strategic partnership is one of the most significant geopolitical development of recent decades. In June 2017, at Prime Minister Narendra Modi's first meeting with President Donald Trump, the pair "resolved to expand and deepen the strategic partnership between the two countries and advance common objectives," most notably "promoting stability across the Indo-Pacific region."1 How likely is it that these two countries can actually cooperate and where is such cooperation most likely to happen? Across the subregions of the Indo-Pacific, Southeast Asia would appear to be an area where the transformation of Indo-U.S. strategic ties would have the most significant implications. For India, Southeast Asia is the most geographically proximate subregion and the focus of its efforts to both "look east" and "act east." For the United States, Southeast Asia historically has been a region where Washington's attention has ebbed and flowed.2 Under the Obama administration, however, both individual Southeast Asian nations and the Association of Southeast Asian Nations (ASEAN) as a whole received enhanced attention at the highest levels. A decade ago, the idea of the United States and India working together in Southeast Asia would have appeared far-fetched. Due to a growing recognition of the congruence of their interests in the region, however, the two countries are increasingly articulating common diplomatic positions on key security challenges. Most prominently, the joint statement made after the Modi-Trump summit in 2017 addressed the maritime disputes in the South China Sea and reiterated "the importance of respecting freedom of navigation, overflight, and commerce throughout the region."3 This high-profile diplomatic signal had been anticipated by some analysts who have long speculated about the close fit between the U.S. "rebalance" to Asia and India's "Act East" policy.4 Indeed, according to former U.S. defense secretary Ashton Carter, the United States focusing westward and India acting to its east have resulted in a "strategic [End Page 53] handshake" between the...