Abstract: Although the Bangladesh-China-India-Myanmar Economic Corridor (BCIM-EC) has the potential to enhance economic and geo-strategic benefits of the four participating countries in the long run, its building process has often been stagnated due to India’s lingering concern about the implications of the Corridor for its national security and, more importantly, to the growing competition among major countries including China, the United States and India. Moreover, there remains ethnic insurgency in Northeast India and Myanmar as well as the Rohingya issue between Bangladesh and Myanmar, which poses lasting security threats to the building of the Corridor. By analyzing the nature of those challenges, this article shows that the emerging Indo-U.S. strategic coalition for checking China’s influence and India’s reluctant stance in building the BCIM-EC are the biggest challenges, whereas neither the ethnic insurgency nor the Rohingya issue can affect BCIM-EC building substantially. Therefore, it is concluded that the BCIM-EC cannot succeed unless China and India can both fully commit to the building process while enhancing all-round cooperation based on their mutual strategic trust. Full text available here.