China’s massive hydropower project on the Yarlung Tsangpo in Tibet has sharpened India’s concerns over the future of the Brahmaputra. India’s proposed 11,200-megawatt Siang Upper Multipurpose Project in Arunachal Pradesh is being considered as a strategic response — but it has triggered fierce resistance from indigenous communities who fear displacement, ecological damage and risks to their ancestral lands. As protests intensify, we examine China’s megadam, India’s water-security concerns, the proposed project’s storage capacity, earthquake and environmental risks, and the demands of the Adi communities. Can India prepare for potential upstream threats while protecting local livelihoods and securing genuine public consent?