This book gives an insight about the theoretical framework of foreign policy. It also spots light on the relations between India and United States through historical lens. As the strategic importance of South Asia increased after 9/11, US started looking for partners in this regions. India became closer to US and raised the slogan "Oldest and largest democracies". This book will highlight all those common factors which brought two states close to each other including China factor. What are the impacts of Indo-US nexus on South Asian security is the main focus of this book.