People's War Theory cannot be executed on water in a contemporary operating environment. The VPA did not efficiently operationalize people's war theory or an all-peoples defense during the Cambodian occupation nor are they in the struggle for sovereignty in the East Sea. Vietnam must move towards an integrated theory of war and a complementary operational doctrine. The next evolution in people's war theory must aggregate elements from theories that focus on joint, maritime, and amphibious elements of warfare. Vietnam will not achieve its policy aims with its current military strategy, because its theory of war does not enable strategic leverage for asymmetric potential on the East Sea. Contents: 1. Introduction 2. Literature Review 3. Methodology 4. Case 1: Vietnam-Cambodian War 1978-1988 5. Case 2: Sino-Vietnam East Sea Action 2011-2016 6. Findings and Analysis 7. Conclusion Vietnam and China adhere to a theory of people's war that evolved from the post-World War II communist revolutions. In the modern context, a theory of people's war and how it shapes Vietnamese national and military strategies on the East Sea lends itself to an analysis of emerging military strategies through the conceptual lens of an all-people's defense. The South China Sea has and will continue to be a critical piece of terrain for the international security environment as a strategic chokepoint for the world's seaborne lines of communication. The February 2015 US National Security Strategy (NSS) continues to articulate the importance of the region and a "pivot" to the Pacific. The NSS commits the United States to freedom of navigation, commerce, and supports peaceful/legal resolutions for disputed claims in the South China Sea. The countries that are physically touching the South China Sea are competing for fishing rights, use of natural resources, and dispersed island chains throughout the waterway. China has infamously claimed the region using the "nine-dash line" that depicts the historical and legal rights to ownership.2 There is considerable research on China's use of modern people's war. The Vietnamese application of people's war in the South China Sea has received little research. The protracted struggle on the South China Sea begins with its name. The world may collectively refer to the body of water south of China and east of Vietnam as the South China Sea, but the Vietnamese refer to the region as the East Sea. The title given to the area by countries with deep historical, political, and military linkages illuminates a friction in approach to control of the East Sea. The Vietnamese theory of people's war and an all-people's defense appears similar on the surface to Chinese methods. However, a closer analysis of conflict and compromise between the two countries indicates their approaches to warfare diverge in context and experience. The Vietnamese perspective of people's war and its application on the East Sea must be analyzed and understood to decipher operational approaches that create balance in the region.